Re: [Sursound] Rode vs Ambeo as ST350 replacement?
On 11/29/22 20:21, j...@bmbcon.demon.nl wrote: Hi everybody, I know this has been gone over before, but now more of you must have experience of the Rode NT-SF1 and the Sennheiser Ambeo mics. I’m thinking of selling my Soundfield ST350 and getting a smaller, more portable mic. I have heard recordings of course, but I haven’t been able to try either mic. It’s more for field recording use, sometimes in the studio. Is there really a bit difference between the two, do you think? or will everyone go “N! Don’t sell the 350!” To get this out of the way: NO! Don't sell your 350. Best localisation of the three, lowest noise. I've owned the Røde (until it was stolen from me), and what's great about it is it comes with a really nice ball gag included, and the price is hard to beat. But the localisation performance and also SNR isn't that great - I was expecting a lower noise floor of capsules that size. Still a *very* decent offer, though. For outdoors, it's wonderful. Never used a series Ambeo, but I've tested a prototype for Neumann (who did the design for SH using KE14 capsules), and the localisation is way better than the Røde due to its smaller size, and it's easier on the pole. Also a bit noisier than the Soundfield, I would say, although I didn't get the chance to make good measurements. A little bit quieter than my tetramic. You can use a simple foam windscreen, but if you want better wind performance, the only real option is Rycote's Baby Ball Gag, which isn't as quiet as a full blimp. Don't know if there's any blimps with lyres big enough to hold the entire Ambeo. I heard they match the capsules, but there is no individual equalisation/calibration. For demanding stuff indoors, I'm sticking to my ST450. -- Jörn Nettingsmeier Tuinbouwstraat 180, 1097 ZB Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
[Sursound] IRT gets it: open-source libraries for object-based audio
Hi *! Haven't checked this out in any detail, but the German Institut für Rundfunktechnik (a sort of science outsourcing provider for public broadcast over here, with an impressive track record of ground-breaking work) have released a substantial body of code on object-based audio under an Apache open-source license: https://lab.irt.de/more-open-source-for-open-object-based-audio-workflows/ If anyone gets interested and finds it useful, please give them a little shout-out - I guess our fellow open-source enthusiasts within those institutions can use some support! All best, Jörn -- Jörn Nettingsmeier Tuinbouwstraat 180, 1097 ZB Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
[Sursound] List of Ambisonic Software
Hi fellow sursounders, the article "List of Ambisonic Software" has been deleted from wikipedia by editorial consensus. Since it contains quite a bit of useful information, I have archived it on my userpage: https://en.wikipedia.org/wiki/User:Nettings/List_of_Ambisonic_Software If someone here feels inclined to adopt this thing and put it in a safe a preferably maintained corner of the internet somewhere, please help yourself. All best, Jörn -- Jörn Nettingsmeier Tuinbouwstraat 180, 1097 ZB Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] 2nd order A-format to B-format equations
On 3/24/19 9:42 PM, Fons Adriaensen wrote: I know tetraproc is GPL'd, but Len has chosen to obfuscate the custom decoding parameters to protect his secret sauce. No, that isn't true. The actual parameters in the preset files are not obfuscated at all, and both tetraproc and octofile contain the code to read the preset files (which are just binary OSC). Thanks for the clarification, and apologies for the misinformation. Best, Jörn -- Jörn Nettingsmeier Tuinbouwstraat 180, 1097 ZB Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] 2nd order A-format to B-format equations
On 3/24/19 1:25 PM, Martin Dupras wrote: Hi, Could anyone point me in the direction of a resource that shows the equations for converting a 2nd order A-format recording into B-format? I would like to convert in realtime from a Core Octomic in software (e.g. PD, Max, SuperCollider) without the use of a plugin. In case vendors are reluctant to share their precise decoding steps, you can always make it work for one particular microphone by measuring the impulse responses of each A-format channel into all the B-format channels, which will give you an 8x9 convolution matrix. It might be a dense matrix, but probably with very short impulse responses, so likely light on CPU. On Linux, my tools of choice are Fons' aliki to measure IRs and edit them for convolution, and jconvolver to apply them in a very efficient way. The joy is that you would be reverse-engineering Fons' octoproc (which might even be GPL'd, I don't know). I know tetraproc is GPL'd, but Len has chosen to obfuscate the custom decoding parameters to protect his secret sauce. Fair enough. I guess the same holds for the Octomic. Facing the choice of understanding C++ DSP code which has been through Fons' brain optimizer or measuring a few IRs, I'd choose measuring any day :-D -- Jörn Nettingsmeier Tuinbouwstraat 180, 1097 ZB Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Anyone ever tried to bypass youtube/facebook360 player Ambisonics decoder?
On 2/21/19 2:18 AM, Aaron Heller wrote: If it is any help, the script I wrote to make YouTube videos from AMB files is here: https://bitbucket.org/ambidecodertoolbox/amb2yt/src Some samples that might help you reverse engineer the format https://youtu.be/eY9DMn8pgGA https://youtu.be/RC4ptd9B-NA You could make a file with isolated W, X, Y, and Z content, upload, then download and see where the channels end up. I vaguely remember Google using AmbiX rather than Furse-Malham, and that might be true for YouTube as well. So take a good look at your normalization coefficients before attempting to decode. -- Jörn Nettingsmeier Tuinbouwstraat 180, 1097 ZB Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Soundfield by Rode plugin
On 12/17/18 12:15 PM, Politis Archontis wrote: Another very sensible approach was presented by Cristoff Faller and Illusonics in the same conference, in a simpler adaptive filter is used to align the microphone signals to the phase of one of the capsules, making them again in essence coincident. IIRC the Super CMIT mentioned by Chris earlier uses just this algorithm by Christof. -- Jörn Nettingsmeier Tuinbouwstraat 180, 1097 ZB Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Comparison Sennheiser Ambeo mic vs. Rode NT-SF1?
On 12/13/18 11:12 PM, Ralf R Radermacher wrote: Yes, but the Sennheiser has electret capsules while the Rode is a 'real' condenser mic. I do agree that electrets have come a long way in recent years. Still, I'd like to know how they compare beyond their noise level. On 12/14/18 10:47 AM, David Pickett wrote: B&K / DPA have been using electrets for more than 30 years. O course, these are perhaps not the same as one can buy for peanuts at Alibaba! The Ambeo uses Sennheiser K-14 if I remember the number correctly. They work very well. I guess unless you want to use a mic in really hot conditions like close to incandescent stage lights (where an electret might lose its charge) or at extremely high SPL (where you might want to use higher polarization voltage on the diaphragm), there is really no problem. Haven't used the Sennheiser mic since I tested a prototype several years ago, but it held up very well. I don't buy this "real condenser" lingo. My subjective experience with the Sennheiser was this: * slightly worse localisation than the Tetramic * slightly nicer tone color out-of-the-box than the Tm (but then there's always EQ and tastes differ) * significantly quieter than my Tm * more "neutral" and a bit less "in-your-face" than the ST450 (which sounds very cinema-y to me) * much nicer and more professional package than my first-generation Tm, easier to have confidence in... * less bulky than a similarly rugged ST450 because no pre-amp box * lighter on the boom than a ST450, but nothing beats the Tm here (if you keep the PPAs down at the or on the recorder) Can't say anything about peak SPL handling, I mostly did street and nature atmos while testing. The prototype ate through batteries like crazy due to its phantom current requirements. I was told there is a fix coming in later batches of the series, don't know what became of it. If you get the chance to test one, do run it on batteries and see if it's a problem for your use case. This is only really relevant in comparison to the Tm, the ST450 uses a lot more power due to external preamp and capsule heating. Best, Jörn -- Jörn Nettingsmeier Tuinbouwstraat 180, 1097 ZB Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Multi-user head tracked binaural ambisonics query
On 11/1/18 11:04 AM, Simon Connor wrote: Hi Sursounders I'm wondering if I could pick some brains if possible… I’m interested in the potential of using head tracked binaural HOA in a gallery setting, but that would support multiple users at the same time (say up to 6 people) so that each could have their own respondent audio experience. Could anyone recommend any Reaper friendly software and cost effective head trackers that would allow for multi-user head tracking? I know that Waves NX offers this but only for FOA and I've been less impressed by the sound of the binaural decoding as yet. I've been very impressed by Audio Ease’s 360 pan suite with their suggested headtracking device but currently this doesn’t offer multi-user functionality. Any suggestions would be very welcome! My goal for 2019 is to work on a Raspberry Pi 3B+ solution for this. Deploy one Pi per user with a USB headtracker and a good sound output stage (such as HifiBerry), then just multicast a suitable HOA stream (using, for example, Fons' zita-njbridge). I'm considering MrHeadTracker from Graz, but to be honest I haven't tried building/porting rendering software yet. Will be glad to compare notes, but won't start working on it before January... -- Jörn Nettingsmeier Tuinbouwstraat 180, 1097 ZB Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Looking for mic advice
On 10/2/18 8:11 AM, Jonathan Kawchuk wrote: Has anyone checked out the Nevaton VR microphone <http://nevaton.eu/nevaton-goes-ambisonics/>? Incredibly low self-noise if you are looking to do nature recording. Curious what the spatial resolution will be like and what calibration looks like. Re: spatial resolution, would anyone even bother with FOA mics for capturing directional impulse responses? Me :) Better the Soundfield in your hand than two Eigenmikes in the bush :) -- Jörn Nettingsmeier Tuinbouwstraat 180, 1097 ZB Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Big Pre-amps?
On 06/04/2018 05:59 PM, Len Moskowitz wrote: A customer is consider using a few OctoMics simultaneously, recording to computer. Each OctoMic requires 8 channels of pre-amps. They'll need up to 72 channels. Ideally, the pre-amps should have digitally-set and gangable trims. Have heard good things about the Horus, too, but never used it. A nice alternative (possibly a bit mor affordable) would be three DirectOut Andiamo MC feeding a dual MADI system, or two and a Mictasy. Btw, nice usage of the word "few" there. Classy. A quick calculation tells me you mean "seven or so". That's the number of SM58s I use on a good day, and I'm very much intrigued if slightly scared thinking of your usecase :-D -- Jörn Nettingsmeier Tuinbouwstraat 180, 1097 ZB Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Open HeadTracking Initiative OHTI - Release announcement
On 05/18/2018 02:56 PM, Bo-Erik Sandholm wrote: I want to present OHTI, a combination of open Software, Firmware and HW for listening to Ambisonic recordings in Ambix format and with a plan for listening to channel based Audio in the future, The Manifesto at https://github.com/bossesand/OHTI/blob/master/OHTI%20v.14.doc describe the current status and the plans for the future on a technical level soutable for sursound members. All the software and descriptions of needed HW is available at https://github.com/bossesand/OHTI The Headtracker is using BLE for communication with the host software and is built with nrf52832 and BNO055 for drift free headtracking. All of the host software is JS/node.js or JS/HTML5 based to allow it to work on many different platforms. We have in this alpha release Ambisonic 2 players implementations with headtracking activated using Omnitone or JSAmbisonics. We also describe how to convert a personal HRTF SOFA file for use with each of the players. We have tested the implementations on Linux (Ubuntu), OSX and Win10 with HTML5 capable Browsers like Chrome and Firefox. We have received support or assistance from a number of members on the sursound list since the slow start in 2014. We hope for continued support and assistance in this effort to make headphone sound more realistic ( out of the head ) and promote surround sound for music and not only in VR context. We also hope that you can make it possible to use this headtracker with other Ambisonic Soundfield Binaural decodes. We do of course also appreciate any corrections or further assistance in development of this concept. thanks! always curious about new tracking approaches. small but unavoidable nitpick: a fscking word document in a github repo? why oh why? -- Jörn Nettingsmeier Tuinbouwstraat 180, 1097 ZB Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Ambix to FuMa conversion
On 04/14/2018 05:53 PM, Fons Adriaensen wrote: On Sat, Apr 14, 2018 at 05:28:57PM +0200, David Pickett wrote: Thanks, Fons. I was hoping it was something as simple as this. I failed to find anything on the internet that expresses the relationships so simply. Did I actually miss a page? Not one I know of. Some of my programs (e.g. Ambdec) do the conversion when required, so I just took these gain figures from my source code. There is https://en.wikipedia.org/wiki/Ambisonic_data_exchange_formats#Reference_table_of_layouts_and_normalisations , which could use a few eyeballs and probably be made a little friendlier. -- Jörn Nettingsmeier Tuinbouwstraat 180, 1097 ZB Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Core Sound Announces OctoMic - First 2nd-order Ambisonics Microphone
On 03/27/2018 10:18 PM, Fons Adriaensen wrote: On Tue, Mar 27, 2018 at 09:08:54PM +0200, Jörn Nettingsmeier wrote: Sweet! A resounding "me too" to Stefan's question about the matrix, since you're one channel short :) Looking at the geometry, I guess you sacrificed the second-order rotationally symmetric component (FuMa R or ACN 08), which seems to be a good choice to me. ACN 6 (= R) actually. Ah crap, it's 8 by Jerôme's counting scheme. Still getting bitten by those after all these years :-D -- Jörn Nettingsmeier Tuinbouwstraat 180, 1097 ZB Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Core Sound Announces OctoMic - First 2nd-order Ambisonics Microphone
On 03/27/2018 03:59 PM, Len Moskowitz wrote: core-sound.com/OctoMic/1.php Sweet! A resounding "me too" to Stefan's question about the matrix, since you're one channel short :) Looking at the geometry, I guess you sacrificed the second-order rotationally symmetric component (FuMa R or ACN 08), which seems to be a good choice to me. What's that disclaimer about third-party PPAs? I mean, your PPA seems to be an integral part of the mic, given that it produces unbalanced signals. Is there any other magic going on there? I wonder if you can get ZOOM to include an octomic firmware in the F8 eventually, as Sennheiser did with their Ambeo mic, that one's mighty handy. (Not that I'm holding my breath, I wouldn't be surprised if there were some exclusive deals at play...) Can I assume that there is an updated version of TetraProc for the followers of the penguin? And looking at the shop, I don't see the Rycote lyre listed yet - is it a generic one that can be had from them, or something custom-made and not quite ready yet? I'm trying to come up with a good business case to order one asap, and since I'm good at fooling myself, it might just happen :-D All best, Jörn -- Jörn Nettingsmeier Tuinbouwstraat 180, 1097 ZB Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] MEMS speakers
On 01/20/2018 01:12 PM, Jörn Nettingsmeier wrote: On 01/19/2018 08:04 PM, Gary Gallagher wrote: Wave field synthesis wall paper? How small does an an audio pixel have to be? The question is more like "how big can you make it?". An audio "pixel" of a square millimetre cannot produce meaningful audio frequencies if suspended in mid-air without a baffle, you would have to get somewhat close to the wavelength. So no million-channel audio interfaces either, I guess the approach would be to use lots of those pixels in unison. How you ensure good airtight coupling between them is one question, and the other is how much excursion you can get. Thiele-Small parameters for silicon cavities, anyone? :-D It's quite a moonshot actually, and if you start thinking about the complexities, that carbon nanosheet paper that came from China a few years back doesn't sound soo far-fetched anymore, where people were producing sound by heating surfaces with an extremely good heat conductivity (so its thermal cycles can be at audio frequencies). Problem there is 100% k2, as it's effectively a half-wave rectifier... Hit send too fast - meant to add that Fraunhofer in Germany has been doing research on MEMS drivers for in-ear systems for a while, and they combine the output of a cascade of laterally compressed nanomechanical cavities in series to drive the eardrum. -- Jörn Nettingsmeier De Rijpgracht 8, 1055VR Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] MEMS speakers
On 01/19/2018 08:04 PM, Gary Gallagher wrote: Wave field synthesis wall paper? How small does an an audio pixel have to be? The question is more like "how big can you make it?". An audio "pixel" of a square millimetre cannot produce meaningful audio frequencies if suspended in mid-air without a baffle, you would have to get somewhat close to the wavelength. So no million-channel audio interfaces either, I guess the approach would be to use lots of those pixels in unison. How you ensure good airtight coupling between them is one question, and the other is how much excursion you can get. Thiele-Small parameters for silicon cavities, anyone? :-D It's quite a moonshot actually, and if you start thinking about the complexities, that carbon nanosheet paper that came from China a few years back doesn't sound soo far-fetched anymore, where people were producing sound by heating surfaces with an extremely good heat conductivity (so its thermal cycles can be at audio frequencies). Problem there is 100% k2, as it's effectively a half-wave rectifier... -- Jörn Nettingsmeier De Rijpgracht 8, 1055VR Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] B-format tap
On 10/13/2017 02:54 PM, Marc Lavallée wrote: More about this solution. The MPV player (http://mpv.io/) have a youtube-dl backend that allows to play youtube videos directly. So first install it, and test it with a youtube URL. Then install the Firefox extension and try it. The source code of the extension is available: https://github.com/antoniy/mpv-youtube-dl-binding.git It could be modified to detect ambisonics content and rewire the audio output of MPV to use an ambisonics decoder. mpv can use jack as output. The command line would look something like this: mpv --ao jack --jack_port=ardour.YoutubeIn.* The "ardour..." thing is a regular expression to match the jack ports, the dot is any single character, dot-asterisk means arbitrarily many characters. Note you may not directly be able to use ambdec, because the channel ordering might get mixed up, so I suggest running ardour or whatever jack-capable DAW you like and hook that up to your decoder. If you cannot configure this in whatever Firefox magic you use, here's a trick: * find the mpv binary and (as root) rename it to mpv.bin or something * where the mpv file used to be (and is now mpv.bin), create a file "mpv" that contains the following: #!/bin/bash mpv --ao jack --jack_port=ardour.YoutubeIn.* $* That's all, now your script (with the jack magic gets called instead, and the $* makes sure it gets handed all parameters originally used. Check out, maybe mpv also has a config file where you can set JACK as default, that would be even simpler. All of the above should work in Linux and OS X, not sure how to do it in windows (but I'm sure it can be done). All best, Jörn -- Jörn Nettingsmeier De Rijpgracht 8, 1055VR Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Video + multichannel audio playback
On 09/04/2017 12:57 AM, Marc Lavallée wrote: https://mpv.io/ https://www.videolan.org/vlc/ Also, consider using JACK to connect a decoder after the player, so that you can store your media in portable Ambisonics format rather than rendered to a particular layout. Greetings on the way home from https://vdt-icsa.de, Jörn -- Jörn Nettingsmeier De Rijpgracht 8, 1055VR Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Multichannel players for permanent installations
On 06/27/2017 07:52 PM, Augustine Leudar wrote: see my post before last for what went wrong. How much are the Joecos ? https://www.thomann.de/gb/joeco_bbr64_dante_blackbox_recorder.htm However, if you go the Dante route, you might as well use an old Minimac with a virtual soundcard (if 32 ch out is enough) and an appropriate Dante converter. Should be cheaper, if you have the Mac lying around, and no less robust if the hardware is otherwise ok. -- Jörn Nettingsmeier De Rijpgracht 8, 1055VR Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Multichannel players for permanent installations
On 06/27/2017 01:52 PM, Augustine Leudar wrote:> Ive been the> computer with multchannel soundcard route and it is not an experience Id> like to repeat. Must be bomb/cleaner/child/adult proof, Can I ask what went wrong? -- Jörn Nettingsmeier De Rijpgracht 8, 1055VR Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Multichannel players for permanent installations
On 06/27/2017 02:53 PM, David Pickett wrote: At 13:52 27/06/2017, Augustine Leudar wrote: >Hi, >I know I've asked this before but maybe there's some new developments. HAs >anyone any suggestions for anything up to a permanent 22 channel >installation (could be two devices started at the same time and set to >loop) . The best suggestion Ive had I think is one of those old hard disk >recorders for use with mixing desks ? Any other suggestions ? Ive been the >computer with multchannel soundcard route and it is not an experience Id >like to repeat. Must be bomb/cleaner/child/adult proof, A second hand Alesis HD24, if you are on a low budget. They are bomb-proof. Iff you can get the appropriate disks, which seem to be fetching collector's prices these days :-D There is also this: https://joeco.co.uk/multi-track-audio-players-products-live-install-joeco/ Played with it at a trade show, my impression was a very good one. Not cheap though. -- Jörn Nettingsmeier De Rijpgracht 8, 1055VR Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Bizarre
On 10/31/2016 12:07 AM, Fons Adriaensen wrote: On Sun, Oct 30, 2016 at 11:40:50PM +0100, Jörn Nettingsmeier wrote: Also, I think things get even funnier when you consider you don't have three pairs of omnis, for a differential receiver along each spatial axis, but rather a tetrahedron of omnis, and the joys of mapping that to B-format. That, in theory, is not so difficult. Problems start in real life. You could make six dipoles, one along each edge. But with 4 inputs you can have only 4 independent signals. Yeah, they are not linearly independent. I wonder how to map them... was thinking you could derive those 6 dipoles independently (in the hope that mismatches could then be compensated for more easily), and then project each of them onto the XYZ space with a little summing matrix. Not that I'd actually want to do that, though - with four MEMs, the prize doesn't seem worth it :-] -- Jörn Nettingsmeier De Rijpgracht 8, 1055VR Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Bizarre
On 10/30/2016 03:09 PM, Sebastià V. Amengual wrote: I could be wrong, but as I understand, as far as the distance between the microphones is much smaller than the wavelength, it is possible to obtain first-order microphones with any kind of directional pattern. Thus, at least for a limited frequency range they could create the four cardioid signals or directly the B format signals, just using linear combinations of the signals (delay and sum). Again, for a limited frequency range... I am not sure how they would manage to get an acceptable directivity at all frequencies... You can, but yes, the frequency range :) Also, I think things get even funnier when you consider you don't have three pairs of omnis, for a differential receiver along each spatial axis, but rather a tetrahedron of omnis, and the joys of mapping that to B-format. I'm trying to model that, but it gets very confusing very quickly... You could make six dipoles, one along each edge. Then in addition to the frightful EQ gains needed to make a fig8 work over a reasonable frequency range, you have additional gains to shoehorn those dipoles into three linearly independent components. Still trying to figure out if that kinda cancels out in the end, but right now my gut feeling is such a beast would be even more sensitive to capsule mismatch than a traditional cardioid array. Add the terrible, terrible frequency response of MEMs with their cavity resonance and not at all omni-directional behaviour, throw in the effects of the (rather larger) circuit boards depicted in the article, and you end up with something that is frightful on so many levels that it might as well be a Hallowe'en joke. I worked on comparing different methods in my master thesis analyzing the performance using different spacing between microphones, just in case anyone is interested on this http://www.diva-portal.org/smash/get/diva2:752195/FULLTEXT01.pdf Thanks! I was also re-reading an excellent article about dipole mics by Mark Williamson that someone posted here a while ago, unfortunately it seems to have fallen off the web... -- Jörn Nettingsmeier De Rijpgracht 8, 1055VR Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Stand alone recorder with built-in mics
On 10/27/2016 03:27 AM, Steven Boardman wrote: More product folks. Nothing to do with me, but just came up on the radar https://www.indiegogo.com/projects/twirling720-vr-audio-recorder#/ Love the name. Should be twice as good as 360. Then again, 1440 would be even better. Anyone? But let's ease off on those guys, they are among the few who actually post specs and a concept that might even work, because people have been testing it since the 70s :-D Neat packaging. -- Jörn Nettingsmeier De Rijpgracht 8, 1055VR Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Bizarre
On 10/28/2016 08:22 PM, Marc Lavallée wrote: Here’s the link to the first “article": https://www.arkamys.com/ambisonic-microphone-ep01/ <https://www.arkamys.com/ambisonic-microphone-ep01/> What a load of bollocks. Four omni capsules spaced closely together will give you... [drum roll]... an omni microphone. So yeah, we've got W, so we're ambisonic :) They probably got inspired by the other loads of bollocks that get attached to VR camera rigs to enable them to be marketed as A/V solutions. Nokia and others do it, so it must work, right? -- Jörn Nettingsmeier De Rijpgracht 8, 1055VR Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] PhD position in acoustic signal processing at Chalmers
On 10/12/2016 01:31 PM, Jens Ahrens wrote: Levitation as well as haptic feedback and audible sound will be achieved using high-intensity ultrasound. I am utterly fascinated. But from a safe distance. ;) -- Jörn Nettingsmeier De Rijpgracht 8, 1055VR Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Native HOA in Pyramix DAW
On 09/06/2016 08:32 PM, Joseph Anderson wrote: Interesting... Some related b<>com links: https://b-com.com/en/mots-cl%C3%A9s/3d-sound https://b-com.com/en/news/whitepaper-audio-other-dimension-virtual-reality https://b-com.com/en/news/bcom-audio-solutions-presented-paris-2016-aes https://b-com.com/en/news/bcom-2-booths-ibc-exhibition year, saw those guys being featured in the "future zone" at IBC in amsterdam a few weeks ago. nice :) -- Jörn Nettingsmeier De Rijpgracht 8, 1055VR Amsterdam, Nederland Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio), Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Oktava A-format microphone?
On 14.07.2016 19:06, len moskowitz wrote: Did you know that Rycote's Baby Ball Gag works fine with TetraMic, as well as their industry standard modular system. fwiw, from recent personal experience, i have nothing but praise for the baby ball gag. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Double MS to B-Format
On 17.07.2016 10:08, Billy Wirasnik wrote: Its a home brew rig for sure. Thrown together very last minute and sadly the day before my Tetramic arrived. It was a Schoeps MK41 sitting 180 on an Audio Technica BP4027 MS shotgun. That is not a double-MS setup. The double-MS needs identical capsules for front and back. When you combine a shotgun and a rear-facing supercardioid, the result is not an omni, but rather something very sad :) The point of B-format processing is to obtain an isotropic sound field. Due to the shape of your W, yours will be so-so in the front, completely unusable at the sides, and possibly excellent in the back. Not a good starting point. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Oktava A-format microphone?
On 13.07.2016 19:22, Albert Leusink wrote: Sorry, I should have done a search firstit has been mentioned here before, about 3 years ago, but no info about how it actually sounds.. http://thread.gmane.org/gmane.comp.audio.sursound/4850 if you're shopping in the medium term, add this one to your shortlist once it's out: http://en-de.sennheiser.com/vrmic-creatorsprogram a little gnome whispered in my ear that it's quite nice. no news on final price and release date yet, but hey... -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Using Ambisonic for a live streaming VR project
On 06/03/2016 02:28 AM, Bob Burton wrote: Very excited to find out to do this. In my research, youtube must render the ambisonic files before playing, so when you live stream, in is stereo. When you play back later, it can be ambisonic. Is there someone else who streams ambisonic live? I did some research just a few weeks ago, and it seemed to me that real-time ingest wasn't really defined yet, only file upload. In any case, it is important to record a full surround b-format at the source, and then the usual usecase it to render to _binaural_, not plain stereo. "native" ambisonic playback only makes sense in a CAVE-like environment, where you have a physical 360° projection. Note however that while the quality of first-order to binaural is quite good because the listener is by definition always in the sweet spot, first-order over speakers can be difficult for multiple listeners when they're far outside the center. On Thu, Jun 2, 2016 at 9:13 AM, Antoine Simon wrote: Hello, We would like to use an ambisonic microphone + a 360° camera for live streaming VR projects. I know how to stream the 360° video in live for a VR headset like GearVR or a Cardboard. But I would like to understand more about how to stream the ambisonic audio. *This is what I understood so far (maybe I'm wrong):* - Ambisonic audio equals to 4 channels in "B" format (W, X, Y and Z) - The player (client side) need to interpret those 4 channels in "B" format into a stereo, depending on the VR Headset position into the 3d space. *My basic Question:* Do you know an exemple or a way to stream that ambisonic audio + a player to interpret the stereo depending on the VR Headset position in realtime? *My further questions:* - Can we transform those 4 channels in "B" format into a 4.0 AAC for the streaming without loosing too much data compared to a WAV PCM? - How to interpret those 4 channels in "B" format into a stereo, depending on the VR Headset position into the 3d space? Thanks in advance for your answers... Best regards, *Antoine SIMON* Live Events Manager, OxygenStream Mob: +33 698 171 875 | Tel: +33 954 826 133 anto...@oxygenstream.fr | http://oxygenstream.fr [image: OxygenStream Website] <http://oxygenstream.fr/> -- next part -- An HTML attachment was scrubbed... URL: < https://mail.music.vt.edu/mailman/private/sursound/attachments/20160602/b16e9f8a/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Coefficients for Octagonal Decoder with CF
On 05/26/2016 03:56 PM, Richard Graham wrote: Hi list! Can anyone point me to a set of coefficients for an octagonal decoder with CF similar to the coefficients on Blue Ripple Sound? quick hack: use one with FL/FR and plug a rotator into the master, set to 22.5°. elaborate hack, the above, then measure impulse responses and plug those into a convolver. saner hack: measure each band separately, and then the "impulse responses" will be single values which you can plug into a scalar dual-band decoding matrix. alternative hack: look at the rotator response and multiply that with the decoder coefficients for FL/FR. i'm only partly serious, but since i'm still haven't mastered ADT, these are the approaches available to me :-D -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Facebook spatial workstation
On 05/24/2016 07:12 PM, Dave Hunt wrote: Hi, <..> I still can't quite grasp the way it functions. Yes, the default output is binaural, via a decoder. It does seem generally convincing, though I've only really scratched the surface. The earlier version could take 1st order B-Format ambisonic files, but not output B-Format. The new version seems to be able to do that, presumably to enable loudspeaker monitoring with a suitable decoder. I haven't checked that app yet, but I worked with a client the other week to get them on track with 360 degree video streaming. As pointed out before, the goal of this app is to provide audio for 360° streams, where the audio follows the video follows the head movements or navigational input from the user. So the binaural output of any tool would only be used for monitoring, the actual delivery format has to be B-format, to enable head tracking on the client side. And B-format (or rather, AmbiX 1st order) is what Google has decided to use for its YouTube 360 format (aka Google Jump). -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Facebook spatial workstation
On 05/24/2016 01:03 PM, Richard wrote: Limited as there’s no Windows support yet How is that a limit? /me ducks and covers... -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Paris AES
On 04/29/2016 09:52 AM, Dave Malham wrote: Just been looking through the Paris AES (June 4-7 2016). Although there's a lot of 3-D oriented sessions, the only mention of Ambisonics I can see so far is in the Heyser Lecture which Rozenne Nicol is giving. Even so, it looks a very interesting programme - I don't think I'll be going, which is a pity - so I look forward to reading reports here. Will be there, will report, would like to meet fellow sursounders for une bière... -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Storage - how do you do yours?
On 04/15/2016 07:09 PM, John Leonard wrote: A question: Most of my recording is now 4 four or six channel 96/24 and currently, I back up from the recorders to bare hard drives via an eSATA docking station, which means that I have an every-increasing pile of hard drives, as I back up every thing important twice. I’ve pretty much standardised on 2TB drives; a mixture of Seagate and Western Digital (I keep telling myself that it’s cheaper than a reel of 1” Ampex 456, but at the rate that I’m piling the drives up, it’s still a bit daunting.) Although this system works pretty well, and I use DiskTracker to keep a record of what’s where, It does mean that I just have a shelf full of 3.5” hard drives, which is a) a bit messy and b) a bit of a risk. The cloud is an option - or at least it will be once I get my super-duper-whizzy even faster Virgin upgrade, but even at the current upload rate of 10 MB, a full drive takes days to upload and then it’s not exactly quick to get it back. Given that I don’t have an educational establishment with huge servers, anyone got any reasonably-priced suggestions for storage? All my "live" data (i.e. the stuff I'm currently working on that has not been delivered to the client yet) sits on a 4TB RAID1 (mirror), plus one "cold copy". Whenever a new generation of harddrives with massively more capacity is coming up, that "working RAID" gets upgraded and the old disks moved into "cold storage" duty. Right now, a RAID1 of 2 8TB disks should be the "sweet spot". Watch out with shingled recording drives: they are slow to write, so not nice for editing, but good for storage. For "cold storage", like you, I keep docking stations around and shelve the drives just like videotapes :) For absolutely critical data, keep one copy off-site, maybe with a trusted colleague who would appreciate the same service? Insert calculations about nuclear blast radius here. Michael hinted at RAID5. I would advise against using it anymore, for the simple reason that rebuilding a huge failed array can take days, during which there is a high load on the system with a high probability of a second drive failure. Go for RAID 6 once your arrays get really huge, it has a double parity mechanism, so any two out of N disks can fail. Of course you only get (N-2) times the capacity of a single drive. And while I'm preaching: don't use hardware RAID controllers, unless you can afford to keep one as a backup in case the first one fails. Their disk formats are not standardized, they are not necessarily compatible to anything you might be able to buy ten years from now. Instead, get a software RAID box. All best, Jörn -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Are mems a good choice for ambisonic microphones?
On 04/14/2016 01:09 PM, Chris wrote: And there's quite a lot more useful and well described material here too. http://www.edn.com/Pdf/ViewPdf?contentItemId=4429422 While it talks about MEMs mics, much of that applies to any very small mic, and the problems of protecting the diaphragm from, yet interfacing it to, the outside world. Chris Woolf Hi Chris, excellent link, thanks! That explains it :) Btw, good to see you guys at Mikroforum the other week! All best, Jörn On 14-Apr-16 11:04, Jörn Nettingsmeier wrote: On 04/13/2016 04:25 PM, Marc Lavallee wrote: I'm looking at this product here: http://www.invensense.com/products/analog/ics-40300-3/ Thanks for posting it, that's the first time I see actual plots of a MEMS microphone. Can anyone explain the reason for the horrible peak at 15k? Is is possible to linearize it to get a useful response above 10k, or does it come with extreme ringing that would make it unusable? Always good to learn about up and coming new technologies, but for this one I'm dusting off and waxing my ten-foot pole... --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Are mems a good choice for ambisonic microphones?
On 04/13/2016 04:25 PM, Marc Lavallee wrote: I'm looking at this product here: http://www.invensense.com/products/analog/ics-40300-3/ Thanks for posting it, that's the first time I see actual plots of a MEMS microphone. Can anyone explain the reason for the horrible peak at 15k? Is is possible to linearize it to get a useful response above 10k, or does it come with extreme ringing that would make it unusable? Always good to learn about up and coming new technologies, but for this one I'm dusting off and waxing my ten-foot pole... -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Re-Routing VST Plugin
On 04/11/2016 10:40 PM, Sönke Pelzer wrote: True that... mighty Reaper. However, life is not perfect until a small Load/Save button shows up there. :) agreed. but another shot in the dark (from ancient memory): doesn't reaper have track templates somewhere? maybe they include plugin and matrix patch setup? -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Re-Routing VST Plugin
On 04/11/2016 05:57 PM, Sönke Pelzer wrote: Hi, Does anybody know a 're-routing' plugin (Windows VST) for the channel order inside a single multi-channel track (Reaper). Doesn't Reaper have a configurable matrix patch before and after every plugin? I can't check right now for lack of a Windows machine on the road, but I seem to remember it's pretty powerful... -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Orah
On 04/08/2016 08:00 PM, Marc Lavallee wrote: Finally, a 3D camera with an integrated FOA microphone? https://www.orah.co/tech-specs/ https://www.orah.co/about/ : "In addition, the ambisonic 3D sound capture capabilities of Orah enable the viewer of the content to locate the origin of the sound source with a VR headset, bringing the feeling of immersion to a stunning new level." https://www.orah.co/ : Looking at the pictures and captions, it says: "Immersive Sound, Four high dynamic-range microphones for ambisonic 3D sound". The capsules (or mems?) look soldered on the sides of PC boards, listening through holes. very far apart, with body resonances that i don't want to imagine. hate to be negative about so much exciting new tech, but "stick n>=4 cheap capsules somewhere and call it ambisonic" seems questionable to me. simple truth of the matter is that as long as video techs add mics as an afterthought, the results are going to suck, badly. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Anyone know anything about this?
On 04/08/2016 04:26 PM, Marc Lavallee wrote: On Fri, 8 Apr 2016 15:13:16 +0200 Jörn Nettingsmeier wrote: They might have very pragmatic reasons: if they know their equivalent input noise is at 30 dB SPL and their capsules barf at 120, then restricting the word length to 96 dB is a perfectly reasonable decision, given the extremely cramped space and the thermal challenges inside the sphere. It does not leave much room for error though, so they better get their analog gains right. It makes sense. Thanks. So what 96kHz refers to? 96 kHz is probably due to the marketing department looking for something that suggests "hi-resolution"... -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Anyone know anything about this?
On 04/08/2016 04:26 PM, Bo-Erik Sandholm wrote: Multi direction binaurals?s? http://recordinghacks.com/microphones/T-H-E-Audio/BS-3D Or beamforming ? a casual glance over the site seems to suggest direct beamforming without an intermediate b-format. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Anyone know anything about this?
On 04/08/2016 02:10 PM, Marc Lavallée wrote: On Fri, 8 Apr 2016 13:00:20 +0200, Jörn Nettingsmeier wrote : On 04/07/2016 08:13 PM, Marc Lavallee wrote: The FAQ says: "audio is recorded in 96 KHz/16 bit quality" I would prefer 48 KHz/24 bit. let's not discuss matters of taste, but rather keep things scientific. 96/16 = 6 48/24 = 2 so theirs is clearly 3x better than yours! Of course! Hertz per bit... Or is it bit per hertz? What's better for marketing? More bits of more hertz? More per bit per second! They might have very pragmatic reasons: if they know their equivalent input noise is at 30 dB SPL and their capsules barf at 120, then restricting the word length to 96 dB is a perfectly reasonable decision, given the extremely cramped space and the thermal challenges inside the sphere. It does not leave much room for error though, so they better get their analog gains right. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Anyone know anything about this?
On 04/07/2016 08:13 PM, Marc Lavallee wrote: The FAQ says: "audio is recorded in 96 KHz/16 bit quality" I would prefer 48 KHz/24 bit. let's not discuss matters of taste, but rather keep things scientific. 96/16 = 6 48/24 = 2 so theirs is clearly 3x better than yours! (i held it during the april foolery, but now it must out :) -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
[Sursound] Invitation to present a technical demo / a workshop / a product presentation at the AES International Conference on Headphone Technologies, 2016, Aalborg (DK)
Sent on behalf of Dr. Alexander Lindau: -- Dear Colleagues, the organizational committee of the International Conference on Headphone Technologies invites you to propose demonstrations, workshops, or thematically suited product presentations. The conference will focus on technologies for headphones with a special emphasis on the emerging fields of Mobile Spatial Audio, Personal Assistive Listening, and Augmented Reality and will be held from August 24-26 in Aalborg, Denmark (http://www.aes.org/conferences/2016/headphones). At the time of writing we have received 42 proposals for scientific contributions which are currently in the process of being double peer-reviewed. The conference program will be complemented by a poster exhibition, a social event and a number of distinguished plenary speakers. For this purpose we can offer a 140m² demo space to be shared by multiple parties. Places for presentation of table top demos (i.e. including only a Laptop, sound card & Headphones) are free of charge. Space for setting up small booths of 4-10 m² may be requested for fees between 400-1000U$. Spaces for larger exclusive booths may be made available on special request. Demo presenters which do not take part in the scientific program will have to register as “Presenters” (Early Bird: 380 U$, see http://www.aes.org/conferences/2016/headphones/registration.cfm). We would like to emphasize that the AES Int. Conf. on Headphone Technologies is a scientific conference in the first place; therefore, it does not host a product fair per se. Proposed product presentations will be reviewed with respect to in how far they feature a thematic bonus to the scientific program. Written proposals (~ 1 page) should include a short description, and a statement about technical requirements and be sent to 2016hp_de...@aes.org by May 31, 2016. Notifications of acceptance will be emailed by July 15, 2016 A Best Demonstration will be elected based on decision of the conference audience. A Best Demo Award including a certificate will be presented at the conference closing ceremony. With best regards Dr. Alexander Lindau Paper’s Chair AES International Conference on Headphone Technologies, Aalborg (DK), 2016 -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Mitglied des Vorstands und Referatsleiter Beschallung im VDT http://stackingdwarves.net -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Decay times and frequency response for control rooms/studios
On 03/30/2016 03:49 PM, Augustine Leudar wrote: Can anyone point me to any kind of standard (BBC/AES etc) for control room room/equipment responses as a whole transfer function. Id like to know what decay times are acceptable. I read somewhere that , within reason, how dead or live a room is not the main issue - its more that the decay times are uniform across frequency spectrum - so you don't have the bass lingering on 100 ms after the mids have dissipated etc , Also in terms of frequency response - the acceptable +/- dB specifications for a room response cheers, Gus EBU Tech 3276 is quite helpful there. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Flac for FOA or amb files?
On 03/26/2016 09:15 PM, Bo-Erik Sandholm wrote: I will use foa in b-format, as far as i remember ambix is Only Chanel order different in for Higher order b-format .. No. AmbiX has a different channel ordering altogether, and its weighting coefficients are different. First-order AmbiX is fundamentally incompatible to POA B-format, although trivially converted. https://en.wikipedia.org/wiki/Ambisonic_data_exchange_formats#Reference_table_of_layouts_and_normalisations Note that Bruce Wiggins pointed out an inconsistency between the weighing coefficients of SN3D (which are taken from Chapman) and the formulation of SN3D by Nachbar et al. (which, if combined as-is, will yield a result that is off by 1/4pi or, as Franz Zotter helpfully pointed out, ~11dB). Not terribly disturbing since it's constant, but something that needs to be fixed for internal consistency. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Static stereo source in rotating soundfield, possible?
On 03/26/2016 05:22 PM, Albert Leusink wrote: Jörn Nettingsmeier writes: i don't see why you would want to do that. the effect will be quite strange... why would any part of the sound mix stay constant wrt head position? the effect would be a bit like rotating the music bed in the cinema every time the camera pans - funny, but certainly irritating. It would be for off-camera audio (voice over, music etc.) that don't have any relation to the camera position/rotation. To quote: "What are you doing?", asked Minsky. "I am training a randomly wired neural net to play Tic-tac-toe", Sussman replied. "Why is the net wired randomly?", asked Minsky. "I do not want it to have any preconceptions of how to play", Sussman said. Minsky then shut his eyes. "Why do you close your eyes?" Sussman asked his teacher. "So that the room will be empty." At that moment, Sussman was enlightened. Imagine a video with an on-camera actor (dialog), a voice over and a music track. You would want the on-camera dialog to match the video position (so counter-rotate) , but the VO and music track will not rotate. I still don't think that makes sense. Certainly it will be detrimental to the proper externalisation of the VR content. If you want to create two disjunct acoustic spaces, do it with _space_, i.e. (lack of) reverb. A close-miked voice-over will be perceptually clearly separated from any surround location recording at all times. If you really want to freak out your users, you could route VO and music to W only - the result will be a source inside your head. But my guess is your brain will just flip you a birdie at that point and hitherto refuse to externalise anything you throw at it, not just the voice-over. if you absolutely have to do it, the only way is to deliver two streams, one head-tracked and counter-rotated, the other not. which means you'd have to have control over the listener's player software. That's what I was afraid of...so I would need 6 channels instead of 4. If and only if you find it actually benefits your production. the only way to get two rotationally invariant signals into the stream is a cardioid pointing up and another one pointing down. if your player ignores head tilt, the result is like summing to mono and mixing into W. if it supports head tilt, the result is likely even worse :- Would that be the same as rotating the encoded stereo stream (set to 0º spread) by 90º vertically? That was not meant to be an actual solution, I was merely stating that with this technique, you could insert two signals into your B-format stream that would be rotationally invariant and could be extracted in the player after the head tracking stage. But they would each spill into your horizontal signal at -6dB, because there is only really room for one extra signal... But if you can do DSP after headtracking, you could also do it right and use two extra channels, iff it actually made sense to do it from a perceptual point of view. So this whole paragraph is hypo³thetical :-D -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Static stereo source in rotating soundfield, possible?
On 03/26/2016 05:58 AM, Albert Leusink wrote: Hello, Is it possible to have a non-rotating stereo source in the ambisonic soundfield, while all the other sources rotate? Let's say I have a stereo music bed in a spherical video that needs to stay in position, while the other elements (dialog, sfx etc.) respond to rotation. are you talking about a head-tracked VR movie? i don't see why you would want to do that. the effect will be quite strange... why would any part of the sound mix stay constant wrt head position? the effect would be a bit like rotating the music bed in the cinema every time the camera pans - funny, but certainly irritating. if you absolutely have to do it, the only way is to deliver two streams, one head-tracked and counter-rotated, the other not. which means you'd have to have control over the listener's player software. the only way to get two rotationally invariant signals into the stream is a cardioid pointing up and another one pointing down. if your player ignores head tilt, the result is like summing to mono and mixing into W. if it supports head tilt, the result is likely even worse :-D -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Furse-Malham to ACN conversion
On 03/23/2016 10:30 PM, Dave Malham wrote: Hi Martin (and Eric!), One very simple thing I would do, before doing anything else, with any system that's playing, as we say, silly bu..ers, is just to play a well localisable sound out of each speaker (on its own) in turn and check that (a) it's coming out of the speaker it should (all connections are correct) and that it sounds like it's coming from the direction you think it should (acoustics not too disruptive). If you really want to be picky, stick a soundfield type mic at the nominal centre point and check correct B format signals are produced for each speaker location at the same time. Only then start worrying about decoders, plugin connections and the rest. I once worked out that in a simple 1st order system driving a cube of speakers, there are 16 million ways of it going wrong, without counting individual component failures in amps, etc. Of course, lots of these ways of going wrong are self cancelling (*both* ends of speaker cable can be connected wrongly, cancelling out the polarity inversion, for instance) which is a darn good job otherwise our job would be near impossible. So, checking the simple things first is a good way to avoid delving around the complex.. in good old steve ballmer tradition: "polarity, polarity, polarity, polarity, polarity, polarity..." if you can't measure it directly, i found it useful to use a stereo phantom source between a reference speaker and the speaker under test. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Furse-Malham to ACN conversion
On 03/22/2016 07:49 PM, Martin Dupras wrote: Today I tried playback sources in third order Ambisonics on a 8+6+1 hemispheric speaker array using Reaper. It didn't quite work as intended so I'm trying to figure out where I've gone wrong. I was using the Blue Ripple TOA-Core panner plugin to position the sound. I understand that Blue Rippler plugins use the Furse-Malham convention. The only decoders that I could find to decode to my specific array (using coefficients that I calculated using the Ambisonics Decoder Toolkit) were the Ambix Plug-ins and AmbDec. I tried Ambix first, which I understand uses the ACN ordering convention. I tried re-ordering the channels based on information that I found here: https://en.wikipedia.org/wiki/Ambisonic_data_exchange_formats#ACN. But that didn't really work. I then tried to run 16 outputs out of Reaper into Jack, and from Jack into AmbDec, again using my ADT-calculated coefficients. I understand that AmbDec uses the Furse-Malham convention, so I would have thought it was compatible with the output of the Blue Rippler plugins. But again, that didn't really work well at all. In both cases the sound was coming from seemingly random places, and a number of positions went practically silent. To debug erratic panning behaviour, start with first order, verify, and work your way up from there. To make sure the error is not in your calculated coefficients, try to use a known-good decoding matrix that approximates what you have, before feeding in your optimized one. With Ambdec, weird things can happen if you connect several ins at the same time using some graphical client, because the order shown in for example qjackctl is lexical, whereas the internal order is different. So you will end up with garbled connections. You can feed an ACN signal into ambdec succesfully if you choose SN3D input scaling _and_ manually connect the inputs correctly. This wikipedia article https://en.wikipedia.org/wiki/Ambisonic_data_exchange_formats has some information on that, and other pitfalls when interfacing different formats. All best, Jörn -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
[Sursound] expressing HRTFs in spherical harmonics
On 01/27/2016 01:56 PM, Jörn Nettingsmeier wrote: On 01/26/2016 11:05 PM, Politis Archontis wrote: Hi Jorn, yes that is correct. I think however that the virtual loudspeaker stage is unnecessary. It is equivalent if you expand the left and right HRTFs into spherical harmonics and multiply their coefficients (in the frequency domain) directly with the coefficients of the sound scene (which in the 1st-order case is the B-format recording). This is simpler and more elegant I think. Taking the IFFT of each coefficient of the HRTFs, you end up with an FIR filter that maps the respective HOA signal to its binaural output, hence as you said it's always 2*(HOA channels) no matter what. Arbitrary rotations can be done on the HOA signals before the HOA-to-binaural filters, so head-tracking is perfectly possible. Wow. That sounds intriguing, thanks! I'll try to wrap my head around the SH expression of an HRTF set in the coming months, hopefully with the help of Rozenn Nicol's book. Sorry to revive such an old thread, but the AES monograph on binaural technology has arrived, and I've begun to study it. Definitely a great resource, recommended: http://www.aes.org/publications/monographs/ Archontis, I'm still trying to understand how to express a set of HRTFS as a SH series. If I understand correctly, all HRTFS for a given ear can be expressed as a function on the sphere, but it would be frequency dependent. So we'd need an extra degree of freedom there, how does that tie in with Ambisonics? One HRTF "balloon" per frequency bin? Also, how do you express the inter-aural time delay conveniently (which, as I've learned from Rozenn Nicol, depends not only on direction, but also on frequency)? Are there papers out there that describe this in detail? Best, Jörn -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Inventory of Ambisonics plug-ins/tools on OS X
On 02/25/2016 02:17 PM, Courville, Daniel wrote: I'm making a list of the Ambisonics plug-ins/tools available on OS X. So far, I have this: am I missing anything obvious? AAX SoundField: http://www.tslproducts.com/soundfield/soundfield-surroundzone2/ Harpex: http://harpex.net/download.html Audio Unit B2X: http://www.radio.uqam.ca/ambisonic/b2x.html Harpex: http://harpex.net/download.html SoundField: http://www.tslproducts.com/soundfield/soundfield-surroundzone2/ VST AAT: http://www.ironbridge-elt.com/products/aat.html ambix: http://www.matthiaskronlachner.com/?p=2015 B2X: http://www.radio.uqam.ca/ambisonic/b2x.html Blue Ripple Sound: http://www.blueripplesound.com/products/toa-core-vst Harpex: http://harpex.net/download.html SoundField: http://www.tslproducts.com/soundfield/soundfield-surroundzone2/ VVAudio: http://www.vvaudio.com/downloads WigWare: http://www.brucewiggins.co.uk/?page_id=78 Reaper ATK: http://www.ambisonictoolkit.net/wiki/tiki-index.php?page=Downloads#JS_FX_plugins_for_Reaper Max Graham Wakefield: http://www.grahamwakefield.net/soft/ambi~/ HoaLibrary: http://www.mshparisnord.fr/hoalibrary/ ICST: https://www.zhdk.ch/index.php?id=icst_ambisonicsexternals Pure Data HoaLibrary: http://www.mshparisnord.fr/hoalibrary/ Plogue Bidule Aristotel Digenis: http://www.digenis.co.uk/?page_id=59 i've added AAT to the list on wikipedia, i think the rest is there. https://en.wikipedia.org/wiki/List_of_Ambisonic_Software -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] AmbiExplorer: no sensors on CM13.0 (Android 6.0 Marshmallow)
On 01/08/2016 11:25 PM, Jörn Nettingsmeier wrote: Hi Hector, hi everone, after a botched mobile phone upgrade (I'm using CM on my Samsung S4 and update frequently), I was forced to redo the phone from scratch, taking the opportunity to move to CM13.0, which is based on Android 6.0 aka Marshmallow. I reinstalled AmbiExplorer from Google Play and had a good look at all the promising new features that I had somehow neglected to play with before :) The only problem is that the sensors have stopped working. I can move the sound field by dragging the head icon, but it does not react to phone orientation anymore. Hadn't used it in a month or so, so I can't be 100% sure it's due to the OS upgrade, but it seems likely. Other apps can access all relevant sensors (I'm using the Physics Toolbox Suite by Vieyra), and I don't have any privacy settings that might interfere with AmbiExplorer. Under Android Settings/Apps/AmbiExplorer, I see it has the permissions to use Location services and storage. I wonder if it is missing an extra permission to access the sensors, but the Vieyra suite doesn't have anything like it either, so I guess permissions can be ruled out. Have you had the chance to try AE on 6.0 on a Samsung? I know this is quite bleeding edge and CM is pretty shaky still, too. So no ill feelings if there's no immediate fix. Maybe I should just go into version junkie detox and stick with what works :-D sorry to revive such an old thread, but i just wanted to remark that sensors in AmbiExplorer have been working again in CM13 nightlies since the last couple of weeks. back to head tracking fun! -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Ambisonic Decoder Design Resources
On 02/24/2016 11:37 AM, /dav/random wrote: Thanks Archontis for mentioning also my little project! Since I moved out from Barcelona Media, I'm developing the project in my freetime and the updated repository changed to: https://github.com/davrandom/idhoa I don't want to SPAM more... so if anyone is interested, just drop an email. can't speak for anyone else here, but personally i would very much like to be informed about this project, and it seems perfectly on topic for sursound. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Different usages, different spaces, different decoders?
On 02/22/2016 09:28 PM, Martin Leese wrote: Peter Lennox wrote: Following on from discussions of decoder solutions: Forgive me if I've missed this (I've been watching sursound for about 20 years, or so - but I just may have missed the odd discussion!) Has anyone systematically studied the interactions between decoders, speaker layouts and particular rooms? Dermot Furlong looked at the last two in the early 1990s. He made a lengthy post to "sursound" in June 1996 describing his work. This post used to be available in my area on the Ambisonia.com site, but it seems to have been deleted. I still have the files, but am not sure of the best way for making them available. I would very much like to have that post. It could be made available on the internet somewhere, and if it is still relevant in the light of recent decoding techniques, used as a reference on the wikipedia page on ambisonic listening rigs. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Different usages, different spaces, different decoders?
On 02/22/2016 11:24 AM, Peter Lennox wrote: Following on from discussions of decoder solutions: Forgive me if I've missed this (I've been watching sursound for about 20 years, or so - but I just may have missed the odd discussion!) Has anyone systematically studied the interactions between decoders, speaker layouts and particular rooms? I ask because, it seems to me that interactions between room acoustics and speaker positioning are known to have significant psychoacoustic (and aesthetic) effects. Informally, I've observed ambisonics working better than it had any right to, in particularly difficult rooms (big reflective empty shoebox, for example). But in respect of particular speaker layouts, (as per the discussion on avoiding too many speaker in the horizontal plane), it seems to me that there could be non-trivial interactions, so that (for arguments' sake) a particular room might benefit from 'this' speaker layout as against 'that' speaker layout. I would seem a monster task to test a wide variety of rooms each with a wide variety of speaker layouts (and I haven't even mentioned the possible variety of speaker dispersion characteristics!) - but in the long run, it needs doing - and sufficient testing might reveal 'families' of layout-room acoustic relationships that can point to underlying causal rules. If it's been done, I'd like to read it, and if it hasn't - sounds like I've just knocked together a precis proposal for a PhD project! to me, the single most obnoxious effect is the phasiness. next is localisation precision, but a long way down. absolutely nobody cares about localisation accuracy, so optimising for minmum angular error seems undesirable to me (unless there is a very specific use case). i've been thinking about modelling the interference patterns to minimize phasiness in a systematic way. haven't done that yet, but now that I learned how to work with the SFS toolkit, i will look at it. after setting up many ambi rigs, these are my working hypotheses: * don't be precise. measure to centimetres, but then add random delay errors in for subjectively nicer reproduction at low orders. this is what needs to be tackled systematically. we need a rigorous technique to dither spatial aliasing optimally. i guess we want the peaks and dips to be smeared out uniformly over a large area. * reverberation is your friend. it smoothes away the phasiness. unless your content has subtle reverb which would be drowned in the room response. * 3D rigs seem to localise worse but sound better for low orders, my guess is it's because of smoother interference patterns. their path length variation is different to that of horizontal speakers across the listening area, which might be helpful. that's why i tend to recommend 3d rigs over higher-order horizontal-only ones, unless you're sure that all your content will be at maximum order. even then, some height is nice. at ICSA 2011, i heard a small IOSONO wfs rig being augmented rather haphazardly with just four small height speakers (which, to the best of my knowledge, were used "to taste" and not in any systematic way), and the improvement was absolutely striking, not for localisation, but for tone color and plausibility of space. * i have a hunch that stacked rings, for all their wastefulness, seem to have very nice interference patterns. for example, the SPIRAL in huddersfield (triple octogon with zenith) is in a ridiculously dry room, but i was quite surprised about its first-order performance, especially since it has way to many speakers for that, in theory. if somebody can suggest any measurements that are feasible in the field, i will gladly obtain them from any future rig that i get to set up. i guess room impulse responses would be the most important piece of the puzzle. maybe we should just sweep each speaker into a tetramic in the sweet spot as a start. with careful analysis, that should contain a lot of information about the speakers and the room. we get free-field response above a few hundred hertz, and below the schroeder frequency, we're in mode land anyways... -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Wireless Solutions for Binaural Event
On 02/21/2016 09:47 PM, Justin Bennett wrote: The solution used in tunnels, caves, mines etc. is to use a radiating cable instead of a normal antenna. This is a coax cable that is designed to 'leak' part of the energy that passes through it, usually by having some holes in the shield (a standard coax won't work). yes, that’s what I meant. There was for a long time a sound art piece on the Afsluitdijk in the Netherlands by Moniek Toebosch that used a leaky coax cable all along the dijk. Drivers could tune into the frequency and listen to Angels. very local and linear coverage! thanks for pointing this out. i had heard about this technique before, but i was assuming that it works because the cable is like a line radiator and it's straight. i'm no radio guy, so i'm applying acoustic principles here and may be totally wrong, but my reasoning is that at uhf, say 600 MHz, you end up with a wavelength of about half a meter. that means the distance between the leaks would have to be small compared to that. fine. should give you a uniform cylindrical field. but what if you follow a u-shaped or zig zag path because that's what the building is like, with a distance between the legs of the u that are a lot longer than the wavelength? i would expect pretty fancy interference patters with loads of complete nulls all over the place. or is there some sort of near-field effect that makes the effect of parallel lengths of wire negligible? -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Wireless Solutions for Binaural Event
On 02/21/2016 03:32 AM, Chris Timpson wrote: Hi all Wondering if anyone has suggestions for a wireless headphone solution? I'm working on a live event that will be a 30mins binaural sound experience in a medieval prison for 24 audience members at a time. We need the audio to begin simultaneously for all audience members and they will be walking around between 3 locations. The distances aren't huge but quite a few walls etc. I've been looking at silent disco type headphones but have concerns about the quality and also that the signal apparently is converted to mono then back to stereo during RF transmission. Anyone tested these? It could be that we use wired headphones with some kind of small playback device that can somehow be remotely triggered to play. There will just be a single audio file that plays from start to finish. Wondering if anyone has tried to build something similar, or perhaps theres an existing solution i've completely overlooked !? I guess the most straightforward approach would be little portable players started at the same time. If you splice a test tone and then five minutes of silence before the program material, you can have attendants start them before handing them to the audience. Another solution might be IR-based systems as used by interpreters. They are quite resilient and easily handle multiple emitters. I don't know what their audio bandwidth is, however. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Wireless Solutions for Binaural Event
On 02/21/2016 12:54 PM, Justin Bennett wrote: thick walls would be a problem though. You could try running antenna wires throughout the space? Don’t know if that would help. i think that would actually make things a lot worse. multiple senders interfere. you can only ever have one transmitter working on a given frequency. if you wanted to hand over to another, it would have to work on a different frequency, and the receivers would have to support that kind of feature. I don't know any headphones that can do it. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Ambisonic Decoder Design Resources
On 02/20/2016 08:31 PM, David Pickett wrote: At 19:53 20-02-16, Bo-Erik Sandholm wrote: >It has been verified by listening test that for FOA it is optimal to not >have too many speakers in the horizontal ring. Look at old mails in the >list. This is a tall order: could you specify approx dates, subject lines, or keywords to search on? Alternatively, please repeat the information here, as it could be of interest. IIRC, one of the BLaH papers also cites listening tests that have found the hexagon to be preferred over square or rectangular setups for first order. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Ambisonic Decoder Design Resources
On 02/20/2016 06:22 PM, Richard Graham wrote: Hi Archontis, I would like to design decoders for 2d and 3d arrays, 1st through 3rd order (at least), both regular and irregular arrays. C code examples would be incredibly helpful as I plan to develop decoders for Pd and Max. Fons' ambdec is GPL, and it comes with a nice set of example setups. It's C++, but the way Fons uses it, it reads pretty much like plain C. After all, a dsp loop is a dsp loop... Most importantly, I’d like to figure out how to calculate these coefficients myself and I am having trouble finding literature on how to do that. I have reached out to a few folks who used their own programs to calculate coefficients. Essentially, I’d like to build my own program in the C programming language. Aaron Heller has a Matlab/Octave toolkit out that will generate matrices for you, and it's completely open. But it relies on quite complex functions of the framework... His solutions are used at CCRMA, to great effect. Probably your best starting point. Richard has one but keeps it proprietary, Fons has one but also doesn't like to part with it (although he has been very generous about generating custom Ambdec setups for people, me included). For the nitty-gritty, check out the papers from recent Ambisonics symposia and the ICSA conferences. Talk to Thomas Musil from Graz for the old-school, lovingly hand-optimized matrix approach, or to Zotter et al. for the All-Rad approach that works for arbitrary setups but is quite complex and kind of brute-forceish. I can dig them up for you if you can't find them. Shortly, I will have access to a 16-channel ring on the horizontal plane and a b-format cube. This system will be modular and configurable into irregular setups, too. nice! but unless you really need extremely high horizontal resolution for research purposes or a truly humongous listening area, a better use for all those speakers would be to make a more or less uniform 3D rig. gets you a nice dodecahedron for full third-order all around. best, jörn -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
[Sursound] Would you like to see Ambisonics at the VDT International Convention 2016?
Hi everyone, following up on the recent thread about (the lack of) Ambisonics at upcoming conventions, I'd like to inform you about this year's VDT International Convention (aka the "Tonmeistertagung"), to take place in Cologne, Germany, Nov. 17-20 2016: http://www.tonmeister.de/index.php?p=tonmeistertagung/2016 The program is not completely in English, but many of the cutting-edge research papers are. I'm a little bit proud to say that through many years of continuous grass-roots efforts, Ambisonics has finally made it onto the radar of the European professional audio community, not the least since the VDT founded and co-hosted the International Conferences on Spatial Audio, which have worked little miracles in bringing the research community and the professional audio market in touch. Consequently, the last VDT convention in 2014 has featured an Ambisonics-capable lecture hall for the first time (3h2v only, but it's a start, and it was for more than 100 people), and we're looking for an excuse to provide one again this year. So please save the date, and keep your workshop ideas and paper presentations coming. It's still a while before the call for papers, but I'd welcome some signs on- or off-list about the kind of interest we can expect to kick some spherical harmonic butt, at a conference that has had a strong reputation for 3D audio topics and drawn thousands of highly skilled visitors, 180 exhibitors and more than 200 paper presentations in the past. And the more interest we see, the more resources we can justify to put into a nice Ambi rig. Disclaimer: I'm a member of VDT and work for them as technical director of the conference. Best, Jörn -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Advice on practicalities of 16-speaker half-spherical arrangement
On 02/09/2016 10:51 PM, Martin Dupras wrote: Thanks for all the responses. Much appreciated. I'll re-phrase the question in light of some of the answers I've been given. I will be using third-order Ambisonics. My aim mostly is to experiment to get a good sense of what is possible with Ambisonics with height. I have experimented successfully with 8-channel planar Ambisonics some time ago. My primary intent is to spatialise multiple monophonic (synthesised) sources using 3rd-order Ambisonics spatialisation, and the playback of mixed sources (spatialised monphonic and stereophonic sources as well as B-format 4-channel recordings.) At this moment in time, I have the opportunity to deploy (next week) a 16-channel array, so I would like some advice on a configuration that would be a good start to experiment with Ambisonics with height. Someone suggested that I consult the wikipedia page on Ambisonics. That is indeed where I got the idea that an "upper hemisphere" setup might be suitable, since I only have on this occasion 16 speakers. There is however no suggestion as to what a suitable hemispherical configuration might be for a 16-speaker array, which is why I asked my original question. yeah, that page is pretty much still in the somewhat incomplete stage i started it in, we should add to it. my advice would be to just use 15 speakers in an 8-6-1 configuration if you want to go for a hemisphere, and to try a icosahedron (with 12 speakers on the vertices) if you want full-sphere, but then only for 2nd order. 3-6-3 can also be nice and simpler to set up. the big advantage of an icosahedron is that most decoders have a suitable setup by default. for hemispheres, you'd need to compute it yourself. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Soundfield ST350
On 02/08/2016 02:03 PM, Steven Boardman wrote: Anyone know what compatible Rycote parts can be used with a Soundfield ST350 / ST450. I have quite a few Rycote sets and am reluctant to purchase another full set from soundfield. They and their distributors have been less than help full in telling me what parts are the same. (they use different part numbers than Rycote). Rycote also can't tell me, as they only make them for soundfield, and say I need to contact them! i don't have the blimp for the st450, but the lyre suspension that came with it is red (in the hope that it'c color-coded for weight). the length of the microphone body including connector and curved cable is about 30 cm (see photo sent in private that's probably not going to make it to the list). best, jörn -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net -- next part -- A non-text attachment was scrubbed... Name: ST450.jpg Type: image/jpeg Size: 314749 bytes Desc: not available URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20160208/cc424dd2/attachment.jpg> ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Never do electronic in public.
On 02/03/2016 02:48 PM, florian.came...@orf.at wrote: (But we shouldn't divert from the original topic.) no, that is frowned upon here :-D thanks for the insightful comments, i was wondering the same... -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Never do electronic in public.
On 02/01/2016 04:25 PM, David McGriffy wrote: The standard I hear in the VR world is 20ms "motion to photons". Minimum frame rate of 60Hz, preferably 90-120Hz. These faster rates do not allow convolution with the full block size of the listen database, though careful truncation should be OK. ? the latency of a convolver has nothing to do with the length of the kernel, only with its own blocksize. with a standard pc, it should be easily possible to get under 3 ms latency, even less if you're prepared to upsample your hrtfs and content to 96k (and burn twice as much cpu, and waste storage). in any case, you can make use of the full length of the hrtfs. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Never do math in public, or my take on explaining B-format to binaural
On 01/28/2016 10:12 PM, Bo-Erik Sandholm wrote: I do understand that HOA can represent resolution of directivity in the mathematic domain better than FOA. But I am starting to suspect we are overworking something when we are talking of order 8 to 15? talking about using order 15 to retain the fine details of hrtfs doesn't mean we have to use 384 loudspeakers. nor will your average smart phone break a sweat when dealing with a very-high-order intermittent stage. but given the care that goes into obtaining precise hrtf sets and the sensitivity of listeners towards coloration, it seems appropriate to represent hrtfs in a way that retains their precision. Is it realistic to even think of measuring individual HRTF response with that angle resolution? i have a set of custom hrtfs measured by ITA in aachen that (off the top of my head, can't check right now) has 3° horizontal and 5° vertical resolution. the whole measuring process took less than 7 minutes, and i'm told they have refined their procedure a lot since then. And is it even neccessary when we know the adaptability of the auditory system? given that even with my own hrtfs, externalisation is still a problem because i can't seem to get the headphone/ear canal equalisation right: yes! yes!! yes!!! that is somewhat orthogonal to localisation precision, but it shows that adaptability has its limits: when the illusion breaks down, it breaks down completely. As stereo works good enough over 45 degrees with 2 speakers and correct psycho acoustic setup and a good recording are we not aiming for a overkill system? if you still think about signal processing in terms of circuit boards and wires or old-school economic elegance, yes. but if the difference is in typing create_HOA_convolver(3) vs. create_HOA_convolver(15) and my phone isn't even getting warm, who cares? i guess it's understood that we're on the very flat end of the diminishing returns curve at order 15. but the cost is getting negligible, _and_ binaural has this habit of failing completely for some people in the presence of very subtle errors. As a normal guy without training in listening for direction of sound sources I suspect I cannot really pinpoint many things in more than +-10 degrees without visual cues. if it was only about directional precision, then i agree, unless we're talking augmented reality: if you're flying this fighter airplane, i'm sure you'd want the "INCOMING!" warning voice to be positioned a lot more precisely than your ability to localize it. I remember old discussion results about ideal number of loudspeakers for horizontal FOA replay being 6 speakers. My goal is to have a device that can play through headphones a stereo or FOA recording and give me a minimum experience of listening to a stereo system or FOA setup with out of head sound and a stable position of the soundstage. I am not certain this is relevant in this discussion thread as we probably have different views of the goals and the path to the goals. well, what do you care about the order in which the hrtfs are represented? you feed FOA in, you get binaural out, and unless your processor starts burning up, you'll never know that inside the black box, some very-high-order stuff might be going on. if by quadrupling the processing power, i can get a robust 5% improvement in the rendering of first-order material, i wouldn't hesitate a second, except in very special cases. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Never do math in public, or my take on explaining B-format to binaural
On 01/26/2016 11:05 PM, Politis Archontis wrote: Hi Jorn, yes that is correct. I think however that the virtual loudspeaker stage is unnecessary. It is equivalent if you expand the left and right HRTFs into spherical harmonics and multiply their coefficients (in the frequency domain) directly with the coefficients of the sound scene (which in the 1st-order case is the B-format recording). This is simpler and more elegant I think. Taking the IFFT of each coefficient of the HRTFs, you end up with an FIR filter that maps the respective HOA signal to its binaural output, hence as you said it's always 2*(HOA channels) no matter what. Arbitrary rotations can be done on the HOA signals before the HOA-to-binaural filters, so head-tracking is perfectly possible. Wow. That sounds intriguing, thanks! I'll try to wrap my head around the SH expression of an HRTF set in the coming months, hopefully with the help of Rozenn Nicol's book. Meanwhile, forgive the man without the heavy ion accelerator that this problem did indeed look like a nail :-D -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Never do math in public, or my take on explaining B-format to binaural
On 01/27/2016 10:02 AM, florian.came...@orf.at wrote: Hello, may I point you to the AES Monograph on Binaural Technology by Rozenn Nicol, published on 2010. Rozenn has nicely summarised most of the issues which have been discussed here lately, and she provides an extensive list of references (more than 200!). Well worth reading (35$ for AES members). i've been eyeing this one for a while (it's advertised in every new issue of the AES journal...), but your recommendation finally made me order it. thanks! -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
[Sursound] Never do math in public, or my take on explaining B-format to binaural
On 01/26/2016 06:36 PM, Stefan Schreiber wrote: 2. < 8 > impulses (for 4 virtual speakers) implies that you don't support 3D decoders (?). If not, why this? (Immersive/3D audio is on the requirement list for VR. It wouldn't make a lot of sense if all sound sources will follow your gaze - looking upwards or downwards.) I think the 8 impulses are used differently. I'm scared of trying to explain something of which my own understanding is somewhat hazy, but here it goes: please correct me ruthlessly. Even if in the end I wish I'd never been born, there might be something to learn from the resulting discussion :) W goes to loudspeaker LS1, LS2, ..., LSn. Same for X, Y, and Z. Each LSn then goes both to left ear and right ear. So you start with a 4 to n matrix, feeding into an n to 2 matrix. The component-to-speaker convolutions and the speaker-to-ear convolutions (the HRTFs) are constant. Convolution and mixing are both linear, time-invariant operations. That means they can be performed in any order and the result will be identical. I guess in math terms they are transitive and associative, so that (a # X) + (b # X) is the same as (a + b) # X, and a # b # c is the same as a # (b # c), where "#" means convolution. So the convolution steps can be pre-computed as follows, where DEC(N,m) is the decoding coefficient of component N to loudspeaker m, expressed as convolution with a dirac pulse of the appropriate value: L = W # DEC(W,LS1) # HRTF(L,LS1) + ... + W # DEC(W,LSn) # HRTF(L,LSn) + X # DEC(X,LS1) # HRTF(L,LS1) + ... + X # DEC(X,LSn) # HRTF(L,LSn) + Y # ... + Z # ... (same for R) which can be expressed as L = W # ( (DEC(W,LS1) # HRTF(L,LS1) + ... + DEC(W,LSn) # HRTF(L,LSn) ) + X # ... + Y # ... + Z # ... (same for R). Note that everything in brackets is now constant and can be folded into a single convolution kernel. That means you can, for first order, reduce the problem to 8 convolutions, going from {WXYZ} to {LR} directly. The complexity is constant no matter how many virtual loudspeakers you use. Of course, that does not take into account dual-band decoding. But if we express the cross-over filters as another convolution and split the decoding matrix into a hf and lf part, we can also throw both halves of the decoder together and do everything in one go. For nth order, you have (n-1)² * 2 convolutions to handle. For head-tracking, the virtual loudspeakers would move with the head (so that we don't have to swap HRTFs), and the Ambisonic signal would be counter-rotated accordingly. Of course that gets the torso reflections slightly wrong as it assumes the whole upper body moves, rather than just the neck, but I guess it's a start. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
[Sursound] Submissions now accepted for 2016 AES International Conference on Headphone Technology
[sent on behalf of Dr Alexander Lindau] Dear colleagues! (sorry for cross-posting) As Papers Co-chairs for the 2016 AES International Conference on Headphone Technology in Aalborg (DK), this summer, we, Alexander Lindau and Jürgen Peissig, are pleased to announce that we are now accepting proposals for full technical papers, poster presentations and technical demos for our conference which is to be held in Aalborg (DK) this summer. For more information and author's kits, please visit the web site http://www.aes.org/conferences/2016/headphones/ and navigate to the 'Paper Submission' subpage. *Conference Topics*(non-exlcusive) *Headphone Design* Headphone Transducers: Technology, Measurement, Microdrivers, Smart Control, Simulation Personalization Additional Sensors Wearing and Listening Comfort *Applications for Mobile Audio* Augmented Reality Mobile Spatial Audio Personal and Assistive Listening Binaural Techniques Up-Mixing Noise Control Monitoring and Analytic Listening *Evaluation* Headphone Quality Quality Standards Automatic Quality Evaluation Perceptual Audio Evaluation Perceptual Targets We invite the submission of full papers between 4 and 8 pages by March 16, 2016. All submitted papers will be double-peer-reviewed before selection. The conference review committee will decide which papers are accepted, and authors will be informed of the decision by May 16, 2016. After revision, final versions of papers must be submitted by July 15, 2016. Additionally, the committee invites interested parties to propose demonstrations, workshops, or thematically suited product presentations. Email proposals should be sent to 2016hp_de...@aes.org <mailto:2016hp_de...@aes.org> by May 31, 2016. Acceptance notifications for demonstrations will be emailed by June 30, 2016. *Awards* A scientific jury will decide about Best Paper Award. Awards for Best Poster and Best Demonstration will be decided about with the help of all attendees and presented at the conference. *Dissemination * No later than 1 month after the conference the proceedings will be made permanently available online from the AES Electronic Library to subscribers. Further on, AES has a pay-to-publish policy in Open Access. If an author wants to make his/her paper openly available to everyone, this is possible by paying a specific Open Access fee. Please see details in http://www.aes.org/openaccess/ Finally, we ask you to share this information with interested colleagues and are hoping to welcome you in friendly Aalborg this summer. Sincerely, Alexander Lindau - Max-Planck Institute for Empirical Aesthetics, Frankfurt/Main Jürgen Peissig - Leibnitz University, Hannover Papers Co-Chairs 2016hp_pap...@aes.org <mailto:2016hp_pap...@aes.org> -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] YouTube adds ambisonics support
On 01/15/2016 10:00 PM, Martin Leese wrote: Andres Cabrera wrote: Very interesting. I'm wondering if it's worth considering separating the order for horizontal vs. vertical (instead of a single unified order). This mixed order scheme, specifying #H and #P, has the disadvantage that as a source leaves the horizontal, its sharpness degrades rapidly to that of the height-order. An alternative scheme, which does not have this problem, is "Complete mixed-order sets". This would also require two numbers to be specified, #H and #V, and is described at: https://en.wikipedia.org/wiki/Mixed-order_Ambisonics#Complete_mixed-order_sets_.28.23H.23V.29 However, I don't know of anybody who has experience with decoding such sets. Fons's decoder can handle that, and iirc it comes with examples. This scheme is particularly useful for stacked rings. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
[Sursound] AmbiExplorer: no sensors on CM13.0 (Android 6.0 Marshmallow)
Hi Hector, hi everone, after a botched mobile phone upgrade (I'm using CM on my Samsung S4 and update frequently), I was forced to redo the phone from scratch, taking the opportunity to move to CM13.0, which is based on Android 6.0 aka Marshmallow. I reinstalled AmbiExplorer from Google Play and had a good look at all the promising new features that I had somehow neglected to play with before :) The only problem is that the sensors have stopped working. I can move the sound field by dragging the head icon, but it does not react to phone orientation anymore. Hadn't used it in a month or so, so I can't be 100% sure it's due to the OS upgrade, but it seems likely. Other apps can access all relevant sensors (I'm using the Physics Toolbox Suite by Vieyra), and I don't have any privacy settings that might interfere with AmbiExplorer. Under Android Settings/Apps/AmbiExplorer, I see it has the permissions to use Location services and storage. I wonder if it is missing an extra permission to access the sensors, but the Vieyra suite doesn't have anything like it either, so I guess permissions can be ruled out. Have you had the chance to try AE on 6.0 on a Samsung? I know this is quite bleeding edge and CM is pretty shaky still, too. So no ill feelings if there's no immediate fix. Maybe I should just go into version junkie detox and stick with what works :-D All best, Jörn -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Sennheiser Easy 3D Recording and Modeling
On 01/06/2016 06:36 PM, Courville, Daniel wrote: « Sennheiser realizes that content is king and that for any new technology to gain traction, it must be easy to develop in. Sennheiser is therefore looking to help content creators take advantage of their 3D audio platform with easy-to-use recording and modeling tools. On the capture front, Sennheiser will feature a virtual-reality microphone. Unlike traditional microphone designs, the new mic will capture high-quality audio in four quadrants. Sennheiser says the mic was designed in coordination with VR content producers. The VR mic is scheduled to launch in the third quarter of 2016. In 2017, Sennheiser will ship a software plug-in that will be bundled with the same mic for VR content post-production. » From http://www.techhive.com/article/3019706/home-audio/sennheiser-launches-new-flagship-headphones-the-hd-800-s-and-moves-into-the-3d-audio-space-with-amb.html Too bad they kicked the Eigenmike guys out :-D Those who do not understand spherical harmonics have to reinvent it... -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] The Mike Skeet Collection
On 12/20/2015 12:00 PM, Richard G Elen wrote: I wonder if any of you can think of anyone who might be able to give this landmark collection a home, or if you can pass this information on to someone who might have thoughts on the subject. How much of it is digitized? I would be willing to host any digital material provided that the copyright situation is clear. I could also propose to the VDT to designate some webspace. If the legal heirs are willing to release this under some reasonably open license (CC-BY?), it might be a great resource. If digitizing is required, I know people who could do it, but then the question is who's going to dig through the archives and ship the stuff? -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Wireless speakers
On 12/17/2015 01:27 PM, Augustine Leudar wrote: I may have posted it before but maybe things have changed. I do a lot of multichannel site specific work sometimes I use speakers up to a hundred metres away from the control center. I currently use Mackie SRM450s and miles and miles of xlr cable which is inconvenient to say the least (think cherry pickers and risk assessments that resemble Phd theses etc etc) . Is there currently any wireless pa or even smaller speakers that can work wireless (I would love to go wireless on both small and large isntallations) . I know I can use seinheizer headphone units but I was wondering if there was a speaker with build in wireless that is relatively compression free (ie not bluetooth!) plus 32 Seinheizer units plus speakers is too costly at the moment. All the wirless speakers Ive seen (eg Alto) only allow stereo - there does not seem to be a system that can deal with multiple discrete channels. Jorn did you mention such a system ? Anyone else care to chime in ? I look forward to the day when I hear the question "Grandad - what's an audio cable ?" oh yes :) when you say "multichannel", and at the same time mention such huge distances, it would be interesting to learn whether you need fixed phase relationships between the speakers (as in an ambisonic or stereophonic playback situation), or have singular sound objects that do not need to maintain strict timing with respect to their neighbours. if it's mostly singular speakers each doing their own stuff, i guess wifi streaming as suggested by marc would be a good option. although i've never tried multicast outside the lab, and certainly never over wifi. maybe it doesn't even have to be multicast then, just synchronized streams on the sender side, and keep the receiver buffers within the maximum allowable time difference between streams. icecast in combination with some jack stream source (ezstream or ices2) should do the job. when you want to get fixed-phase playback over several receivers, things get difficult. but maybe just one receiver for each group of speakers requiring fixed-phase sync would help already? i've just begun playing with the new raspberry pi 2 in combination with an edimax 7711-UW wireless usb dongle (each one will cost you less than 50€ including psu, case, and sd card). there's the problem that the onboard sound is crap and there's no usb 2.0, so i'm using the HDMI audio out (eight channels) in combination with something like https://www.ligawo.eu/ligawo-6518770-hdmi-audio-extractor-dac-7-1-5-1-2-0-analog-audio/a-6518770/ haven't measured this thing yet (i'm not using it for anything critical), and it sure isn't great but usable, and for the price who'd complain. one of those would enable you to run third-order horizontal ambisonics over wireless without jumping through fiery hoops. all best, jörn -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] vertical precendence and summing localisation (wallis and lee 2015)
On 12/15/2015 03:32 AM, Stefan Schreiber wrote: In our discussion before we have found convincing evidence and arguments that head motion should be relevant even to obtain improved vertical localization. Just to set the record straight again: evidence is not to be found on sursound. Evidence is found in the lab. :-] Hat-tip to those who actually do the grunt work that forms the basis of sursound sermons. If sound sources are immovable, their positions can't be determined precisely, because the brain needs them moving (movement of the source or subconscious micro-movements in the listener's head), which helps to determine a sound source position in the geometrical space. (?!) Why quote such questionable statements? Modern systems of reproduction of positioned 3D sound utilize HRTF functions forming virtual sound sources, but these synthetic virtual sources are spot. In the real life the sound mostly comes from large sources or composite ones which can consist of several individual sound generators. Large and composite sound sources allow for more realistic effects in comparison with spot sources. A spot source can be successfully applied to large but distant objects, for example, a moving train. But in the real life when the train is approaching the listener it's no more a spot source. (See One of our postgrads (Dan Peterson <https://dxarts.washington.edu/people/daniel-peterson>) has been working on a doppler-panner that includes diffusion filtering and the proximity effect. ) These two are orthogonal. The first quote talks about sources being physically spread out (e.g. composed of multiple point sources along a line or area), while the second talks about what happens if a point source approaches the listener. The third group consists of the sound tone parameters. This can help the player define what the walls are made of, what is the air density in the environment etc. Every material reflects and absorbs certain frequencies. These parameters emulate such absorption and reflection. They are relative frequencies (LF - Low Frequency and HF - High Frequency) within which changes can be made. For example, metallic walls reflect more frequencies than wooden ones, and the HF level will be lower for them than for emulation of wood. For example, the workshop has the following parameters: 362Hz LF and 3762 Hz HF; a wooden room has the LF at 99 Hz and the HF at 4900 Hz. Finally, there are parameters controlling the effect of Room LF and HF frequencies (in dB). This subgroup also contains Decay factor for LF and HF, and Air Absorption HF factors. This is games design, not acoustics. Done properly, it should look something like http://www.audioborn.com/. A new company spun off from a research effort at ITA/RWTH Aachen, and their demo at ICSA 2015 was mighty sweet. It is a safe bet that specifically AR/VR will require a solid understanding of acoustics and human audio perception. They will have to find improved ways to reproduce surround sound (including 3D audio) via headphones and loudspeakers. Thanks for pointing this out. :-] -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] vertical precendence and summing localisation (wallis and lee 2015)
On 12/10/2015 04:59 PM, Peter Lennox wrote: It does imply that an ambisonic panner plugin that incorporates spectral manipulation would be more efficacious noo! if it's an ambisonic panner, it doesn't change the spectrum. if it changes the spectrum, it's not an ambisonic panner :) -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] vertical precendence and summing localisation (wallis and lee 2015)
On 12/09/2015 03:00 PM, Jörn Nettingsmeier wrote: i've attached the paper, since it is open access. well, i meant to, but apparently the attachment got eaten. here it is: http://www.aes.org/e-lib/browse.cfm?elib=18040 -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
[Sursound] vertical precendence and summing localisation (wallis and lee 2015)
On 12/08/2015 09:07 PM, Peter Lennox wrote: no -percedence effects include a range of phenomena. But precedence in the median plane isn't quite as effective as in the azimuthal plane, according to Litovsky, Rakerd, Hartmann et al, but is still quite effective and so not negligible. So I'd like to understand what Lee (Huddersfield) was saying, to compare. i've attached the paper, since it is open access. i guess i misrepresented it a bit, because i was being sloppy about distinguishing between precedence effect and summing localisation. however, wallis and lee conclude: "Additionally, no evidence could be found to support the operation of the precedence effect in median plane stereophony. In the present study the only occasions whereby stimuli were localized at the position of the ear- lier emitting loudspeaker were due to the pitch height ef- fect. There was also no consistent effect of time panning observed, with localization judgments for the broadband source becoming more biased towards the upper loud- speaker as ICTD increased, as opposed to the lower." [the upper speaker was always lagging behind the lower in this experiment.] in comparing the results with litovsky et al, it should be pointed out that while both were conducted under anechoic conditions, the stimuli used by wallis and lee were long noise snippets with 1s fade-ins and fade-outs rather than clicks, with no transient information at all (which seem designed to test the presence of summing localisation), so i guess they are not in direct contradiction. it just shows that the musical reality will be somewhere in between... Certainly, in respect of producing phantom imagery in the vertical, I've found this to be quite effective (though often slightly more vague than in horizontal) which would explain why periphonic ambisonics works at all - and this seems to be a related issue to the precedence one i found that vbap/stereophonic vertical localisation is excellent on speaker positions (because it gets the spectral cues right), and unusable anywhere else. 3rd-order ambisonic vertical localisation seems uniformly so-so throughout the elevation range, which to me is preferrable... -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net -- next part -- A non-text attachment was scrubbed... Name: 18040.pdf Type: application/pdf Size: 299653 bytes Desc: not available URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20151209/d9d9ec4c/attachment.pdf> ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] OZO? vertical precedence
On 12/08/2015 01:47 PM, Peter Lennox wrote: Couldn't find the full paper again - but there's this one in full: https://www.pa.msu.edu/acoustics/litovsky.pdf The abstract ends "...models that attribute the precedecence effect entirely to processes that involve binaural differences are no longer viable" The researchers are known as excellent contributors to the corpus of psychophysics (Ruth Litovsky did the defninitive review of precedence effects). So I would be interested to examine the differences in their findings and Huddersfield's thanks, very interesting! a quick glance makes me very curious, i'm looking forward to reading this tonight. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] OZO? vertical precedence
On 12/07/2015 02:31 PM, Peter Lennox wrote: But see: Localization dominance in the median-sagittal plane: Effect of stimulus duration Roberto M. Dizon and Ruth Y. Litovsky Received 19 June 2003; accepted for publication 22 March 2004 interesting! i wonder: Lead-lag pairs of noise bursts were presented from locations spaced in 15° increments in the frontal, median-sagittal plane, with a 2-ms delay in their onsets, for source durations of 1, 10, 25, and 50-ms. does this mean they used the same noise source, where one channel was actually delayed, or the same noise source and one channel was just faded up later ("onset delay" could be read this way), or different noise sources altogether? in order to investigate "phantom source" mechanisms, it should be the same noise source, delayed, which is likely what they did, but i can't check this paper unfortunately. Intermixed with these trials were single-speaker trials, in which lead and lag were summed and presented from one speaker. Listeners identified the speaker that was nearest to the perceived source location. so this is a simple "either/or" decision, not a continuum of possible phantom source locations. or put differently: not summing localisation, but something like a precendence effect. ok. i could hypothesize that the initial phase of 2ms from one speaker only is enough information to localize the source, and that the lagging signal is not contributing any more cues. if so, that would not really contradict lee et al. they go on to say With single-speaker stimuli, localization improves as signal duration is increased. the single speaker case is not relevant to the discussion really (although it's a nice touch to add this to the experiment). it just means that if get more time to pinpoint a single source, localisation performance improves. very well. but this could be read as implying "in two speaker stimuli, there was _no_ improvement of localisation as the signal duration is increased". which seems to suggest that indeed, the localisation process is over and done with during the initial 2ms of only a single speaker playing. to test this, one would need to use a coherent signal in both speakers that starts at the same time, but one is delayed relative to the other. maybe by delaying a noise source and fading it in at the same time in both speakers. otherwise, we're really only looking at onset transients. > Furthermore, evidence of elevation compression was found with a dependence on duration. With lead-lag pairs, localization dominance occurs in the median plane, and becomes more robust with increased signal duration. this general statement would contradict my interpretation above. is this paper available somewhere? this one however leaves me scratching my head: These results suggest that accurate localization of a co-located lead-lag pair is necessary for localization dominance to occur when the lag is spatially separated from the lead. i can't imagine what this means. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] OZO?
On 12/06/2015 11:46 AM, Jörn Nettingsmeier wrote: On 12/05/2015 05:26 PM, Stefan Schreiber wrote: I wrote: "8-channel ... hedgehog", which is/was already some form of educated guess. See: http://www.hauptmikrofon.de/HW/TMT2012_3DNaturalRecording_Theile_Wittek_2012_11.pdf, pg. 19. This hedgehog layout really fits to the microphone openings of the Ozo camera... btw, since you're quoting this very interesting article, it has been partly superseded by recent research of lee at al. at huddersfield (see latest JAES), who found that there is _no_ vertical precendence effect and that interchannel time differences in vertically spaced loudspeakers do not contribute to localisation in any way. helmut is aware of this and has presented a much more compact 8-channel mic array at ICSA 2015 in graz, where the top and bottom mics are practically coincident. i should have mentioned that the main reason for schoeps to move away from vertically spaced arrays was not localisation (as mentioned elsewhere, wittek's main interest is ambience in the height channels), but the evidence presented by lee that such spacing does not produce any noticeable difference in AB comparisons. so there is no reason to put up with the additional bulk of vertical spacing. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] OZO?
On 12/07/2015 12:18 AM, Steven Boardman wrote: Just a little point here. I thought the amount of movement ones head can cover vertically is more than it can cover in any other plane. This is obviously not including moving the rest of the body at the same time. This being so, and generally having the ground for reflections, it allows us to work out any confusion. Especially coupled with a slight tilt. Surely hearing what is below is very important, probably more than above, and as such there must be an important mechanism to determine it. the natural vertical motion is to tilt one's neck. this does not change the orientation of the ear spacing, only the angle of pinnae and the direction of the torso/shoulder reflections. the discussion was about inter-channel time differences in vertically spaced speakers not resulting in inter-aural time difference cues at the ears, unless you bend your neck to the sides and then up/down. this is a very unnatural movement. i do use it from time to time to check for errors in complex loudspeaker systems, but it usually results in bystanders asking if i'm ok. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] OZO?
On 12/07/2015 02:55 AM, Stefan Schreiber wrote: Your plots refer to an empty sphere, don't they? no, fons' plots are about a rigid sphere with omni mikes in the surface. Take for example the 8kHz response, which is the most directive one in the set. It's something like 3.5 dB down at 90 degrees. Apart from the narrow peak at the back, that's subcardioid. See above. We currently don't know the exact frequency responses... the point is that you are dealing with omni microphones, and the only directivity that you can work with other than matrixing several capsules is the acoustic shadow of the sphere. And? This is exactly the case here. (IRT cross in two dimensions and the 8-channel hedgehog in the described cuboid form are isotropic. All 12 microphone stereo angles are 90º. A cube is a Platonic solid, "as everybody knows".) stefan, i think you are confused about the fact that the hedgehog or any other open microphone arrays employ directional microphones. the OZO cannot, because it is a rigid sphere with no way for a second acoustic path to each capsule. The 'hedgehog' doesn't produce anything like that, nor is it meant to. It does and is meant to! this is not the case. the eight-supercards hedgehog is not meant to be rotated ever. it has a 1:1 mapping from mics to speakers. rotating it will give massive shifts both in source width and timbre. the design goal of Theile's arrays is to minimize crosstalk and ensure well-defined decorrelation between speaker channels, not isotropy. it is intended to produce ambience only. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] OZO?
On 12/06/2015 07:44 PM, Kees de Visser wrote: On 6 Dec 2015, at 11:46, Jörn Nettingsmeier wrote: btw, since you're quoting this very interesting article, it has been partly superseded by recent research of lee at al. at huddersfield (see latest JAES), who found that there is _no_ vertical precendence effect and that interchannel time differences in vertically spaced loudspeakers do not contribute to localisation in any way. helmut is aware of this and has presented a much more compact 8-channel mic array at ICSA 2015 in graz, where the top and bottom mics are practically coincident. Perhaps I've missed it but no-one seems to have mentioned head movements. head movements are certainly important, but mostly for horizontal lateral localisation. you would have to stretch your neck to very odd angles in order to make use of vertical ICTD, and at the same time lose horizontal ITD (although the latter might not be a problem since localisation perception seems to be constant once a suitable set of cues has been "collected", as long as no contradictory cues show up). -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] OZO?
On 12/06/2015 06:14 PM, Stefan Schreiber wrote: Jörn Nettingsmeier wrote: btw, since you're quoting this very interesting article, it has been partly superseded by recent research of lee at al. at huddersfield (see latest JAES), who found that there is _no_ vertical precendence effect and that interchannel time differences in vertically spaced loudspeakers do not contribute to localisation in any way. ? This is supposed to be new? Methinks there can be only ILD and spectrum cues to enable height perception (but no ITD cues), because the ears are positioned in the same plane. No vertical precedence: Could be very much related to this simple observation. (I guess IC cues will also not matter.) well, obvious in theory, but nobody in the 3d audio world seemed to be aware of it, and now lee has done the deed and pulled the rug from under all those vertically spaced arrays... the "new" part is that somebody actually got around to disprove it, in a rigorous listening test. Do I miss s.th.? no. but there is great value in moving something from the "everybody knows that..." into the "rigorous listening tests have unambiguously proven that..." realm. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] OZO?
On 12/05/2015 05:26 PM, Stefan Schreiber wrote: I wrote: "8-channel ... hedgehog", which is/was already some form of educated guess. See: http://www.hauptmikrofon.de/HW/TMT2012_3DNaturalRecording_Theile_Wittek_2012_11.pdf, pg. 19. This hedgehog layout really fits to the microphone openings of the Ozo camera... btw, since you're quoting this very interesting article, it has been partly superseded by recent research of lee at al. at huddersfield (see latest JAES), who found that there is _no_ vertical precendence effect and that interchannel time differences in vertically spaced loudspeakers do not contribute to localisation in any way. helmut is aware of this and has presented a much more compact 8-channel mic array at ICSA 2015 in graz, where the top and bottom mics are practically coincident. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] OZO?
On 12/05/2015 07:06 PM, Stefan Schreiber wrote: Fons Adriaensen wrote: On Sat, Dec 05, 2015 at 04:26:05PM +, Stefan Schreiber wrote: See: http://www.hauptmikrofon.de/HW/TMT2012_3DNaturalRecording_Theile_Wittek_2012_11.pdf, pg. 19. This hedgehog layout really fits to the microphone openings of the Ozo camera... * The hedgehog is at least twenty times as big. Hardly... Theile's and Wittek's arrays rely on directional microphones. It is not practically possible to achieve directionality from capsules flush-mounted into a sphere, because the rear acoustic path that effects the cancelleation is missing. So any directional effect is either due to matrixing à la Eigenmike or due to baffle effects as described by Fons. Now that I see a hi-resolution picture for the first time, I can't say I'm much excited by the audio capabilities this thing can possibly have. For that price, let's hope they see the light and partner with mh or Duraiswami and deliver something that really kicks butt in the audio domain... -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] OZO?
On 12/05/2015 10:14 AM, Fons Adriaensen wrote: Remains the question of _how_ to actually use the available signals to produce anything surround. Linear beamforming is limited to LF (due to aliasing). The only way I see is some rather complicated non-linear 'logic' decoding. This kind of thing is still a research topic. use two diametrically opposite mics with the sphere as a stereo baffle, and then crossfade to other pairs as the viewer turns? i guess with some help from a capsule in front and in the back you could even fake some binaural front/back cues to reduce confusion. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] OZO?
On 12/04/2015 08:56 PM, Bo-Erik Sandholm wrote: http://www.williamsonic.com/DipoleMic/ as often I am too fast to post :-) I found the article again on a practical differential microphone for DIY. thanks, excellent article! -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] OT: Opportunities for Study and Funding at the University of Birmingham / BEAST
On 11/21/2015 11:15 AM, Dave Malham wrote: Not quite sure how we got from defining acousmatic music to film sound, but... For the record, we got here from Scott announcing study opportunities (a hazy after-image of the original intention of this thread is still visible in the subject line). :-D -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Advice on new loudspeaker array... Genelec 8010 speakers?
On 10/22/2015 08:27 AM, Augustine Leudar wrote: Bah... (; hello Charlie hope you're well ! I just realised the x32 has 32 ins but only 22 outs you can expand it but probably end up paying more than madi or adats... FWIW, there even is a MADI I/O card for the X32/M32. The IEM Graz has one, I got to play with it at ICSA. Works. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] SQ QUAD
On 10/21/2015 03:14 PM, Richard wrote: That is very true, and there never will be. I have a marvellous algorithm that will restore old shellacs to their original 10-octaves full surround beauty, but since the world is what it is, I'm not going to show it to you. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] ADAT vs. MADI
On 10/16/2015 11:37 PM, Augustine Leudar wrote: I've been using them for four years and not experienced those problems (apart from original a da 8000's PSU problems) . The four adat set to slave are controlled by the raydat master clock no need for Wordclock. Agreed, this particular setup works well in my experience, too. The problem with ADAT for pro environments is that you cannot do distance and you cannot have patchbays (well, you can try with Toslink connectors, but it's very unreliable). In fact many people seem to regard external master clocks as snake oil. Im not going there. If you have really crappy clocks, an external master helps. But if you have any RME equipment, you already have a very good word clock generator, no need to pay for an extra one. What I'm saying is that some implementations of ADAT are notoriously bad at locking and syncing (Yamaha desks come to mind - I've had to wordclock them time and again because they were unable to sync to ADAT reliably). So I would prefer having wordclock sync everywhere, which in the case of the ADA8200s requires an extra wordclock splitter since they don't have WC outs. Cable length is not a problem as I have computer and adats in the same rack so cable length is not an issue. Well, if you can wire the ADAT once, inside a single rack, and never touch it again, you're probably fine. As for signal to noise ratio well I've seen this discussed quite a lot with pre amps but rarely these days with dacs. Thd and "noise " is well below audible levels in both units - I can point you to measurements of ada800 if your interested certainly it held its own against more expensive units. It's true that the ADA8k is good enough for most applications, but the extra price of a better converter does get you another 10-15dB less THD+N, plus the THD at least in the old 8000s was quite nasty. I've just replaced an 8000 with an Andiamo in my mixing environment, and the difference is quite audible there. Probably not in your average live venue, though. Haven't had the chance to hear the new 8200s yet, from what I heard they're a lot better. The one place I do concede is the cables are a pain but if you set it up right and dont move it there shouldn't be any problems . My rig is mobile do the cables are annoying but not 2 thousand pounds worth of annoying. I guess this is why large multichannel installations such as the wfs systems at Salford university or game of life because the extra cost of madi is not worth the gain in performance (which audibly is none). Still i like the idea of one box out of curiosity does the Andiamo supply balanced outs ? Of course. Due to space restrictions (it's 32 AD/DA in one rack unit), the balanced ins and outs are D-SUB-25. A bit of extra hassle - I made my own breakouts for it. You can get them from RME or Directout, but they are quite expensive. But since I'm also using it in the studio, the D-SUBs actually quicker to connect than individual XLRs. And the new firmware comes with a complete matrix router that spans all analog and MADI ins and outs. Quite handy, and you can run it MIDI-over-MADI, so you don't need an extra cable there. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
[Sursound] spherical mic array order balancing
On 10/16/2015 06:27 PM, David McGriffy wrote: I've been thinking about how this discussion might apply to a couple of things I'm working on and it seems to me there are two different problems here. First, there is the issue of higher order mics often not really being higher order at low frequencies. Nor at high frequencies because of spatial aliasing... But isn't this really a problem of encoding and not decoding? It seems like we shouldn't have to know anything about the mic once we are in B-format. And such considerations would not apply to synthetically panned higher order signals, right? Yes, that is the sad thing about B-format from spherical microphone arrays. They are not truncatable, since the upper orders are increasingly band-limited. You have to balance the spectrum by equalizing the lower orders accordingly, so that if you use for example the full fourth-order output of the Eigenmike, you arrive at a reasonably flat energy spectrum. But if your listener assumes she or he can truncate the signal set to third or second order due to lack of speakers, they will lose more treble than bass by doing this. I wonder if it's possible to put some fake LF borrowed from the lower orders into the higher ones, so that the spectrum is flat for each order, with the understanding that the directional information will be wrong... But I'm not sure I'm seeing all the implications of this... -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
Re: [Sursound] Advice on new loudspeaker array... Genelec 8010 speakers?
On 10/16/2015 08:34 PM, Fons Adriaensen wrote: Next Ambdec (already in use here, and to be released soon) can do this. <..> 1. Bandsplitting, four options: - single band - single band with sub xover - dual band - dual band with sub xover so in the latter case you'd have 3 bands. The sub filter is 4th order. 2. For each band you can add as many matrices as you want, each of them handling user defined subsets of inputs and outputs. 3. Matrix outputs are added, near-field compensation, delay and gain control are done for each output. Processing can be multi-threaded on SMP hardware. The 'sub' band you could use to drive subs, or to crossover to a lower order decode using the full- range speakers. Of course if you want to do both and dual band as well, you'd need four bands. I'll consider that if there is some press^H^H^H^H^H interest. Consider this interest :-D Where do I sign up as alpha tester? (a lousy one since I don't have too many speakers at the moment...) I don't think four bands are strictly necessary... If there are subs, it seems an odd choice to additionally spread the low-mids across mid-hi speakers. Better to move the xover a bit higher if the mid-hi speakers need some more help. -- Jörn Nettingsmeier Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT http://stackingdwarves.net ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.