Re: [Sursound] Chasing flies with ambisoinics? (was Re: microphone epiphany ?)
On 05/29/2012 08:24 PM, Bearcat M. Şandor wrote: This touches on something i've wondered for a while now. Discrete surround always sounds as though it's in a fixed ring to me. Sounds are always the same distance away. I've experianced that with binaural recordings as well. Is there a surround sound method that will reproduce actual depth enough so that you could track the movment of a fly in a room? I'd love a system where i could hear a fly moving towards my face, veering off a few inches away, moving at a diagonal to 5' away then zig-zaging back and around my head. Would the lack of a visual component effect that strongly? I can still locate a fly without seeing it. Can ambisonics do that with a good mic for the W? doing it correctly requires very high orders, or a very dense wfs system. all first order ambisonics could do is take a lucky shot at psychoacoustics, and then it may work well for a few people, but certainly not for the majority of listeners. -- 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
Re: [Sursound] Chasing flies with ambisoinics?
This is also something I've been wondering about and trying to achieve in sound installations. A fly landed on a microphone once when I was recording in the jungle and when played back it sort of worked - sort of - but I do think the cognitive visual factors (the sound installation was in a large indoor jungle at the eden project) helped enormously with believability - but anyone listening carefully would have heard a fly about 1 foot high ! I am told Wavefiled synthesis what you decribe , though haven't heard it myelf - I will be building a small WFS setup this summer - quite looking forward to hearing it. Another low tech solution which is really crude but would probably work would be to have a tiny speaker on an invisible string and pulley system pulling it round the room. We are considering introducing fireflies to the sound installation this year and that was one idea that crossed my mind Realistic proximity is a tricky thing to achieve ! FA This touches on something i've wondered for a while now. Discrete surround always sounds as though it's in a fixed ring to me. Sounds are always the same distance away. I've experianced that with binaural recordings as well. Is there a surround sound method that will reproduce actual depth enough so that you could track the movment of a fly in a room? I'd love a system where i could hear a fly moving towards my face, veering off a few inches away, moving at a diagonal to 5' away then zig-zaging back and around my head. Would the lack of a visual component effect that strongly? I can still locate a fly without seeing it. Can ambisonics do that with a good mic for the W? Thanks, Bearcat -- next part -- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 198 bytes Desc: not available URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20120529/b153f60d/attachment.bin ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20120530/352e76fd/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Chasing flies with ambisoinics?
One thing to bear in mind is that the perception of proximity is far easier to achieve with (fairly rapidly) moving sources. If you get the changing patterns of simulated early reflections right, the ear/brain will focus on the consistent cues (early reflections) and tend to ignore the inconsistent ones like the direct to reverb ratio. Unfortunately, once the sound stops moving, the direct to reverb ratio becomes more consistent, so However, with any loudspeaker based system, you are continually battling against the loudspeaker radius (a.k.a. reverberation radius or critical distance) problem - that is, the sound from a loudspeaker (or loudspeakers) always tries to sound like it is coming from not less than the distance of the loudspeaker, simply because (one of) the strongest distance cue is the ratio of direct to reverberant sound. It's easier if you have a very dead room and the soundscape you are trying to reproduce has noticeably more reverberation, since you can then get the direct-to-reverberant ratio more closely right. Not that it's easier with WFS or HOA to get some of the other cues right, such as wavefront curvature and this helps greatly - but is not a panacea. There are only two ways (at present) that I am aware of in which you can, even theoretically, do it - short of physically having moving loudspeakers. The first is individually headtracked binaural synthesis over headphones, the other is the use of steerable spots of sound produced by crossing, modulated ultrasonic beams - a bit like Holophonics http://www.holosonics.com/ Acoustic Spotlights but with more widely spread transducers, so that the demodulation only occurs where the beams cross. Dave On 30/05/2012 14:10, Augustine Leudar wrote: This is also something I've been wondering about and trying to achieve in sound installations. A fly landed on a microphone once when I was recording in the jungle and when played back it sort of worked - sort of - but I do think the cognitive visual factors (the sound installation was in a large indoor jungle at the eden project) helped enormously with believability - but anyone listening carefully would have heard a fly about 1 foot high ! I am told Wavefiled synthesis what you decribe , though haven't heard it myelf - I will be building a small WFS setup this summer - quite looking forward to hearing it. Another low tech solution which is really crude but would probably work would be to have a tiny speaker on an invisible string and pulley system pulling it round the room. We are considering introducing fireflies to the sound installation this year and that was one idea that crossed my mind Realistic proximity is a tricky thing to achieve ! FA This touches on something i've wondered for a while now. Discrete surround always sounds as though it's in a fixed ring to me. Sounds are always the same distance away. I've experianced that with binaural recordings as well. Is there a surround sound method that will reproduce actual depth enough so that you could track the movment of a fly in a room? I'd love a system where i could hear a fly moving towards my face, veering off a few inches away, moving at a diagonal to 5' away then zig-zaging back and around my head. Would the lack of a visual component effect that strongly? I can still locate a fly without seeing it. Can ambisonics do that with a good mic for the W? Thanks, Bearcat -- next part -- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 198 bytes Desc: not available URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20120529/b153f60d/attachment.bin ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound -- next part -- An HTML attachment was scrubbed... URL:https://mail.music.vt.edu/mailman/private/sursound/attachments/20120530/352e76fd/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound -- These are my own views and may or may not be shared by my employer /*/ /* Dave Malham http://music.york.ac.uk/staff/research/dave-malham/ */ /* Music Research Centre */ /* Department of Musichttp://music.york.ac.uk/; */ /* The University of York Phone 01904 322448*/ /* Heslington Fax 01904 322450*/ /* York YO10 5DD */ /* UK 'Ambisonics - Component Imaging for Audio' */ /*http://www.york.ac.uk/inst/mustech/3d_audio/; */ /*/ -- next part
Re: [Sursound] Chasing flies with ambisoinics?
Wow - thats real startrek material right there Dave ! I was letting my imagination wander in a similar area the other day and was wondering if the beating/harmonics caused by two beams of electromagnetic waves could somehow excite the air where their paths crossed causing a sound to eminate from that spot. Although it may sound a bit out there I found out from a PHD student that there some Russians doing something vaguely similar already except they are doing it the other way round - using ultrasound propogated in a liquid to create light : http://www.myspace.com/video/12k-line/evelina-domnitch-dmitry-gelfand-quot-xenon-wind-quot-camera-lucida-dvd/7806818 On 30/05/2012, Dave Malham dave.mal...@york.ac.uk wrote: One thing to bear in mind is that the perception of proximity is far easier to achieve with (fairly rapidly) moving sources. If you get the changing patterns of simulated early reflections right, the ear/brain will focus on the consistent cues (early reflections) and tend to ignore the inconsistent ones like the direct to reverb ratio. Unfortunately, once the sound stops moving, the direct to reverb ratio becomes more consistent, so However, with any loudspeaker based system, you are continually battling against the loudspeaker radius (a.k.a. reverberation radius or critical distance) problem - that is, the sound from a loudspeaker (or loudspeakers) always tries to sound like it is coming from not less than the distance of the loudspeaker, simply because (one of) the strongest distance cue is the ratio of direct to reverberant sound. It's easier if you have a very dead room and the soundscape you are trying to reproduce has noticeably more reverberation, since you can then get the direct-to-reverberant ratio more closely right. Not that it's easier with WFS or HOA to get some of the other cues right, such as wavefront curvature and this helps greatly - but is not a panacea. There are only two ways (at present) that I am aware of in which you can, even theoretically, do it - short of physically having moving loudspeakers. The first is individually headtracked binaural synthesis over headphones, the other is the use of steerable spots of sound produced by crossing, modulated ultrasonic beams - a bit like Holophonics http://www.holosonics.com/ Acoustic Spotlights but with more widely spread transducers, so that the demodulation only occurs where the beams cross. Dave ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Chasing flies with ambisoinics?
Of course, the other way is to attach a small, high power speaker to a trained fly Dr Peter Lennox School of Technology University of Derby, UK tel: 01332 593155 e: p.len...@derby.ac.uk -Original Message- From: sursound-boun...@music.vt.edu [mailto:sursound-boun...@music.vt.edu] On Behalf Of Augustine Leudar Sent: 30 May 2012 15:18 To: Surround Sound discussion group Subject: Re: [Sursound] Chasing flies with ambisoinics? Wow - thats real startrek material right there Dave ! I was letting my imagination wander in a similar area the other day and was wondering if the beating/harmonics caused by two beams of electromagnetic waves could somehow excite the air where their paths crossed causing a sound to eminate from that spot. Although it may sound a bit out there I found out from a PHD student that there some Russians doing something vaguely similar already except they are doing it the other way round - using ultrasound propogated in a liquid to create light : http://www.myspace.com/video/12k-line/evelina-domnitch-dmitry-gelfand-quot-xenon-wind-quot-camera-lucida-dvd/7806818 On 30/05/2012, Dave Malham dave.mal...@york.ac.uk wrote: One thing to bear in mind is that the perception of proximity is far easier to achieve with (fairly rapidly) moving sources. If you get the changing patterns of simulated early reflections right, the ear/brain will focus on the consistent cues (early reflections) and tend to ignore the inconsistent ones like the direct to reverb ratio. Unfortunately, once the sound stops moving, the direct to reverb ratio becomes more consistent, so However, with any loudspeaker based system, you are continually battling against the loudspeaker radius (a.k.a. reverberation radius or critical distance) problem - that is, the sound from a loudspeaker (or loudspeakers) always tries to sound like it is coming from not less than the distance of the loudspeaker, simply because (one of) the strongest distance cue is the ratio of direct to reverberant sound. It's easier if you have a very dead room and the soundscape you are trying to reproduce has noticeably more reverberation, since you can then get the direct-to-reverberant ratio more closely right. Not that it's easier with WFS or HOA to get some of the other cues right, such as wavefront curvature and this helps greatly - but is not a panacea. There are only two ways (at present) that I am aware of in which you can, even theoretically, do it - short of physically having moving loudspeakers. The first is individually headtracked binaural synthesis over headphones, the other is the use of steerable spots of sound produced by crossing, modulated ultrasonic beams - a bit like Holophonics http://www.holosonics.com/ Acoustic Spotlights but with more widely spread transducers, so that the demodulation only occurs where the beams cross. Dave ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound _ The University of Derby has a published policy regarding email and reserves the right to monitor email traffic. If you believe this email was sent to you in error, please notify the sender and delete this email. Please direct any concerns to info...@derby.ac.uk. ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Chasing flies with ambisoinics?
In the early seventies, I remember Trevor Wishart doing a spatial audio piece by putting battery powered cassette recorders in suitcases and having the performers move around carrying them (and I'm sure there have been other such...) However, back to the present - given the progress the military are making on miniaturising spy drones, these would probably be a better bet than the average fly :-) Dave On 30/05/2012 15:19, Peter Lennox wrote: Of course, the other way is to attach a small, high power speaker to a trained fly Dr Peter Lennox School of Technology University of Derby, UK tel: 01332 593155 e: p.len...@derby.ac.uk -Original Message- From: sursound-boun...@music.vt.edu [mailto:sursound-boun...@music.vt.edu] On Behalf Of Augustine Leudar Sent: 30 May 2012 15:18 To: Surround Sound discussion group Subject: Re: [Sursound] Chasing flies with ambisoinics? Wow - thats real startrek material right there Dave ! I was letting my imagination wander in a similar area the other day and was wondering if the beating/harmonics caused by two beams of electromagnetic waves could somehow excite the air where their paths crossed causing a sound to eminate from that spot. Although it may sound a bit out there I found out from a PHD student that there some Russians doing something vaguely similar already except they are doing it the other way round - using ultrasound propogated in a liquid to create light : http://www.myspace.com/video/12k-line/evelina-domnitch-dmitry-gelfand-quot-xenon-wind-quot-camera-lucida-dvd/7806818 On 30/05/2012, Dave Malhamdave.mal...@york.ac.uk wrote: One thing to bear in mind is that the perception of proximity is far easier to achieve with (fairly rapidly) moving sources. If you get the changing patterns of simulated early reflections right, the ear/brain will focus on the consistent cues (early reflections) and tend to ignore the inconsistent ones like the direct to reverb ratio. Unfortunately, once the sound stops moving, the direct to reverb ratio becomes more consistent, so However, with any loudspeaker based system, you are continually battling against the loudspeaker radius (a.k.a. reverberation radius or critical distance) problem - that is, the sound from a loudspeaker (or loudspeakers) always tries to sound like it is coming from not less than the distance of the loudspeaker, simply because (one of) the strongest distance cue is the ratio of direct to reverberant sound. It's easier if you have a very dead room and the soundscape you are trying to reproduce has noticeably more reverberation, since you can then get the direct-to-reverberant ratio more closely right. Not that it's easier with WFS or HOA to get some of the other cues right, such as wavefront curvature and this helps greatly - but is not a panacea. There are only two ways (at present) that I am aware of in which you can, even theoretically, do it - short of physically having moving loudspeakers. The first is individually headtracked binaural synthesis over headphones, the other is the use of steerable spots of sound produced by crossing, modulated ultrasonic beams - a bit like Holophonics http://www.holosonics.com/ Acoustic Spotlights but with more widely spread transducers, so that the demodulation only occurs where the beams cross. Dave ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound _ The University of Derby has a published policy regarding email and reserves the right to monitor email traffic. If you believe this email was sent to you in error, please notify the sender and delete this email. Please direct any concerns to info...@derby.ac.uk. ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound -- These are my own views and may or may not be shared by my employer /*/ /* Dave Malham http://music.york.ac.uk/staff/research/dave-malham/ */ /* Music Research Centre */ /* Department of Musichttp://music.york.ac.uk/; */ /* The University of York Phone 01904 322448*/ /* Heslington Fax 01904 322450*/ /* York YO10 5DD */ /* UK 'Ambisonics - Component Imaging for Audio' */ /*http://www.york.ac.uk/inst/mustech/3d_audio/; */ /*/ ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Chasing flies with ambisoinics?
On Wed, May 30, 2012 at 02:10:22PM +0100, Augustine Leudar wrote: but anyone listening carefully would have heard a fly about 1 foot high ! This magnification effect has been reported many times. I wonder how much it has to do with playing back at too high levels. We do associate LF energy and size. Too much of it and the source 'must be' big. Ciao, -- FA A world of exhaustive, reliable metadata would be an utopia. It's also a pipe-dream, founded on self-delusion, nerd hubris and hysterically inflated market opportunities. (Cory Doctorow) ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Chasing flies with ambisoinics?
Kind of already happening ! Not exactly a virtuoso performance but still pretty cool : Miniature flying robots play James Bond theme : http://www.youtube.com/watch?v=_sUeGC-8dyk No if we could just get the noise levels of the robots down and fix a small speaker on their backs I think interesting things could occur On 30 May 2012 15:47, Dave Malham dave.mal...@york.ac.uk wrote: In the early seventies, I remember Trevor Wishart doing a spatial audio piece by putting battery powered cassette recorders in suitcases and having the performers move around carrying them (and I'm sure there have been other such...) However, back to the present - given the progress the military are making on miniaturising spy drones, these would probably be a better bet than the average fly :-) Dave tic Spotlights -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20120530/d98fd64a/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Chasing flies with ambisoinics?
Is there a surround sound method that will reproduce actual depth enough so that you could track the movment of a fly in a room? A while back I started making a series of simultaneous binaural and 1st-order soundfield recordings. The purpose is to compare them in reproduction, with a couple of goals in mind. I'll leave those goals aside for the moment. The rig is comprised of a dummy head constructed according to ITU-T P.58 and either a DPA-4 (for fixed recording situations) tetrahedral microphone or a Tetramic (for mobile recordings). A necessary intermediate step has been to perform a diffuse-field calibration of both the soundfield microphones and the dummy head. That has now been done. I made need to do it again, but at the moment I have something that seems satisfactory. One of those recordings was of a fly buzzing around the manikin. As soon as Ambisonia is up and running again I'll post some of those recordings. Eric Benjamin ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Chasing flies with ambisoinics?
The problem is, a sound sources as close to your ear as a mosquito is essentially a mono signal on one ear, you practically hear nothing on the other ear. That's pretty much impossible to do with anything than a headphone setup, or some phase cancelation while your head is clamped down such as not to move. So the realism gets lost on things that sound loud without being loud, because they are so damn close to an ear. I wonder if there's a formal specification as to the distance and volume of objects that can be reasonably accurately modeled with a speaker array given the constraints of the human head size. Ronald On 30 May 2012, at 14:29, Augustine Leudar augustineleu...@gmail.com wrote: Thats probably it - but if it had been quieter it wouldnt have been heard at all or rather it would have sounded like a distant bee . The thing is when an insect flies really close to your ear its a really loud almost a physical sensation .I was trying to get that effect when I fly or mosquito flies really close to your ear and you brush it away. I would be difficult to get those sort of pressure levels any quieter from a loudspeaker on the other side of the path - Under the circumstances I was prepared to accept a one foot fly but to be realistic its not going to sound anything like real life without WFS or something similar (Im all for the training a fly solution myself) . On 30 May 2012 18:24, Fons Adriaensen f...@linuxaudio.org wrote: On Wed, May 30, 2012 at 02:10:22PM +0100, Augustine Leudar wrote: but anyone listening carefully would have heard a fly about 1 foot high ! This magnification effect has been reported many times. I wonder how much it has to do with playing back at too high levels. We do associate LF energy and size. Too much of it and the source 'must be' big. ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
[Sursound] Catching the same fly twice (and a curious question)
speaker arrangement (horizontal only) while playing a live recording of persons talking at eight equally-spaced locations around a Soundfield mic. Upon playback, I’ll place the Soundfield mic in the four-speaker arrangement, record this, and then listen to the recording of the recording. How much localization info do you believe will be lost? Could be fun, plus I’m a firm believer in learning by doing. Thanks for reading, Eric -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20120530/081156c8/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Catching the same fly twice (and a curious question)
Although I don’t ascribe to a single 'school' of psychology, I do buy into James Gibson's idea that man (and animals) and their environments are inseparable (this is at the heart of Ecological Psychology). I think (or at least hope) that James Gibson's ideas are slowly making their way into the field of audio engineering. What I like about Gibson's ideas is that they remove the emphasis on physical modelling. For example, the perception of how far away a fly is significantly determined by what _other_ sounds exist at the same time. For example, a fly always has low loudness. If one can hear a fly very clearly and the environmental sound levels are high ... then something rings wrong. But it is not just the relative loudness ... it is also the entire acoustic ecology ... ecological consistency etc. An other aspect of Gibson's ideas that are interesting concerns the difference between mediated environments and non-mediated environments. Gibson argues that it is impossible for a mediated environment to ever be confused with a non-mediated environment... no matter how good the technology. The reasons are environmental again. Ofcourse, that doesn't mean that there cant be a 'suspension of disbelief' ... but some argue that the suspension of disbelief is the domain of art, not science. It is the expression (of the art) that fools the perception (not the stimuli). Here is where I find 'fault' or room for improvement with a lot of controlled laboratory experiments: this has been argued by a few researchers. Personally, I am starting to question that the centrality of 'direction', not just evident in audio synthesis interfaces but also evident in the underlying theory of ambisonics (and in Gerzon's ideas), is not actually just a direct result of the limitations of a laboratory based scientific understanding of sound perception. I wonder if perhaps direction is *not* that important to spatial audio. Ofcourse, it is a part, but is it central? This view leads to the questioning of the value of higher order ambisonics. Anybody tried this? I think I’ll give it a go using a four speaker arrangement (horizontal only) while playing a live recording of persons talking at eight equally-spaced locations around a Soundfield mic. Upon playback, I’ll place the Soundfield mic in the four-speaker arrangement, record this, and then listen to the recording of the recording. How much localization info do you believe will be lost? Could be fun, plus I’m a firm believer in learning by doing. would be interesting to do it over and over again .. effectively doing calculus on the effect (or bias) of the microphone. Very similar concept to Alvin Lucier's composition I am sitting in a room ... except Lucier is amplifying the effect of the room .. and it is significant... and this suggests that the experiment should be done in an anechoic chamber ... because you will be capturing not just the effect of the microphone, and the limitations in the decoding, as well as the character of the speakers, but also the character of the room. Etienne Thanks for reading, Eric -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20120530/081156c8/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound -- http://etiennedeleflie.net -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20120531/6b2ced5e/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
