Re: [Sursound] Distance perception
On Tue, Jul 26, 2011 at 10:26:49PM -0400, Marc Lavallée wrote: How large is the resulting stereo image? As large as you make it, see below. Is your technique documented somewhere? Can it work with a horizontal hexagon? With 2rd order AMB? Sure. There isn't much to document, just set up your AMB system and use two AMB panners for the L and R signals. Ciao, -- FA ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Distance perception
Apart from the damping problem which has been very well laid out by Fons, there is another factor which can come into play and which I documented in an article in Hi-Fi for Pleasure many years ago. The fact is that many poorly constructed cables, when hit with a bit of power, will actually produce sound themselves. Those of us who are ancient, like me, will remember that in the days before printed circuit board construction - so things were point-to-point wired - oscilloscopes (in particular but not exclusively), were very prone to this and would often sing quite happily when hit with an audio signal. So, when I first heard the sound from the cables I though it was the scope I was using and it took me a while to realise it wasn't. The produced sound suffers from extreme variations in frequency response and is very 'hysteric', in that there is often a level below which it doesn't happen at all and over which it suddenly starts to sing. It's to long ago to quote figures, the experimental approach I used was not terrible rigorous and the whole subject needs (properly) reinvestigating but it's still something to be aware of. Fortunately, as Fons says, decent mains cable would be fine - at least it was then. The one I really liked when I was testing speaker cables was ordinary flat ribbon cable with alternate conductors paralleled up. Low resistance, low inductance, didn't produce its own noises and fitted nicely under carpets (or you could use the colour coded variety and use it as a feature in the room - not sure if it would necessarily improve the SAF, though :-) Dave On 27/07/2011 05:57, Bill de Garis wrote: On 26/07/11 3:41 p.m., Sampo Syreeni wrote: On 2011-07-26, Fons Adriaensen wrote: I certainly don't want you to waste your money on fancy speaker cables. Never thought otherwise. That's obviously never been what we do here. ;) But resistance does matter, so a good cross section such as 2.5 mm^2 puts you on the safe side. What I was trying to ask is, what's the real problem with resistance, especially with regard to a passive speaker and a modern, A/B class solid state end stage? I mean, I don't really see cable resistance shifting their operating point much, even with feedback, within the audible range. What is it that I'm missing? I swapped out some lamp cable on the speakers of a stereo setup some years back with some cheap stranded speaker cable I bought at Costco. Each core of the cable was about 3 times the cross sectional area of the lamp cord (each core of the speaker cable was about 3/16 in dia). The distances were not great, 5 or 6 feet. The improvement in stereo imaging was huge. Previously the image had wandered around between the speakers seemingly at random, now it was rock solid at the point wherever it was when I recorded it. ___ 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 432448*/ /* Heslington Fax 01904 432450*/ /* 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] speaker cable resistance [was Distance perception]
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Re: [Sursound] Distance perception
On 26 Jul 2011, at 17:00, sursound-requ...@music.vt.edu wrote: Date: Mon, 25 Jul 2011 20:18:42 -0400 From: Marc Lavall?e m...@hacklava.net After reading this difficult thread (I'm replying with a new title), I have simple questions about room sizes and speaker distances. Imagine two rooms with proper acoustic characteristics and treatments for ambisonics reproduction: the first is 3mX4m and the other is four times larger in surface (9mX12m). In both rooms there's a horizontal hexagon of speakers, and 5 speakers are against a wall. When NFC is applied in both rooms, do they sound the same in terms of distance perception when playing the same recording? Or is the same sound object appear to be twice as far in the largest room? As J?rn has pointed out, the effect of the different acoustics of the rooms is hard to eliminate, and speaker placement relative to walls and other surfaces also has audible consequences. Anechoic rooms are hard to achieve, and are rather unpleasant and disturbing to be in. It is would be difficult to do an A/B comparison. So, it is a rather hypothetical, if relevant, question. A better test would be two identical or similar outdoor rigs at different distances matched in level, with the ability to switch between them. The 40' geese phenomenon has been mentioned many times. John Leonard's recording, obviously fairly close perspective, when played on large systems gives the impression of very large geese. No-one seems to have an explanation for this. Possibly it is due to conflicting perceptual cues, visual as well as aural. Even without any visual aspect close sound sources seem 'bigger'. Aural perspective is not the same as visual perspective, though there are some similarities. Visual distance acuity is probably not much better than aural distance acuity. Both rely on comparison, experience and supposition. My hunch, which I cannot back up with formal theory, is that distance perception is relative rather than absolute. So, I would expect the two 'rooms' to sound broadly similar though not identical, assuming 'proper acoustic characteristics' and appropriate NFC. Distance perception would be consistent, though different, in each 'room'. Apart from widening the listening sweet spot, are larger rooms better at reproducing distance cues when using the same speaker configuration? It has been said several times on this list that the size of the sweet spot is related to wavelength and not the size of the speaker rig, and I'm not knowledgeable enough to disagree. Certainly larger rooms have later and lower level reflections, with lower frequency resonant nodes and a more even frequency distribution of the harmonics of those nodes. Speakers can be more easily located away from walls and corners, resulting in direct sound sound from them arriving earlier and being louder than reflected sound. Is distance perception directly related to speaker distances? I suspect that that it is related in the case of ambisonics, though not directly. This is more psychoacoustics than just physics or acoustics. Ciao, Dave Hunt ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Distance perception
years ago (no decades ago) i found what a huge difference it made if the wires were reasonably thick, and cut to be exactly same length. cutting them to same length is problematic with eight loudspeakers (unless the amp sits in the sweet spot) but my next rig, in my own house, in bangalore next year, will have same length wires to all the speakers. umashankar i have published my poems. read (or buy) at http://stores.lulu.com/umashankar Date: Tue, 26 Jul 2011 21:57:49 -0700 From: d...@dgvo.net To: sursound@music.vt.edu Subject: Re: [Sursound] Distance perception On 26/07/11 3:41 p.m., Sampo Syreeni wrote: On 2011-07-26, Fons Adriaensen wrote: I certainly don't want you to waste your money on fancy speaker cables. Never thought otherwise. That's obviously never been what we do here. ;) But resistance does matter, so a good cross section such as 2.5 mm^2 puts you on the safe side. What I was trying to ask is, what's the real problem with resistance, especially with regard to a passive speaker and a modern, A/B class solid state end stage? I mean, I don't really see cable resistance shifting their operating point much, even with feedback, within the audible range. What is it that I'm missing? I swapped out some lamp cable on the speakers of a stereo setup some years back with some cheap stranded speaker cable I bought at Costco. Each core of the cable was about 3 times the cross sectional area of the lamp cord (each core of the speaker cable was about 3/16 in dia). The distances were not great, 5 or 6 feet. The improvement in stereo imaging was huge. Previously the image had wandered around between the speakers seemingly at random, now it was rock solid at the point wherever it was when I recorded it. ___ 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/20110727/2a25f5c3/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Distance perception
my favourite visual image is of a boeing 747. it always seems to fly so slow. we seem to have, in our brains, a 'size' for aircraft, so we can use that to compute speed from angular momentum. so small aircraft wiz by and big ones lumber. what models do we create for sound objects? umashankar i have published my poems. read (or buy) at http://stores.lulu.com/umashankar From: davehuntau...@btinternet.com Date: Wed, 27 Jul 2011 11:01:32 +0100 To: sursound@music.vt.edu Subject: Re: [Sursound] Distance perception On 26 Jul 2011, at 17:00, sursound-requ...@music.vt.edu wrote: Date: Mon, 25 Jul 2011 20:18:42 -0400 From: Marc Lavall?e m...@hacklava.net After reading this difficult thread (I'm replying with a new title), I have simple questions about room sizes and speaker distances. Imagine two rooms with proper acoustic characteristics and treatments for ambisonics reproduction: the first is 3mX4m and the other is four times larger in surface (9mX12m). In both rooms there's a horizontal hexagon of speakers, and 5 speakers are against a wall. When NFC is applied in both rooms, do they sound the same in terms of distance perception when playing the same recording? Or is the same sound object appear to be twice as far in the largest room? As J?rn has pointed out, the effect of the different acoustics of the rooms is hard to eliminate, and speaker placement relative to walls and other surfaces also has audible consequences. Anechoic rooms are hard to achieve, and are rather unpleasant and disturbing to be in. It is would be difficult to do an A/B comparison. So, it is a rather hypothetical, if relevant, question. A better test would be two identical or similar outdoor rigs at different distances matched in level, with the ability to switch between them. The 40' geese phenomenon has been mentioned many times. John Leonard's recording, obviously fairly close perspective, when played on large systems gives the impression of very large geese. No-one seems to have an explanation for this. Possibly it is due to conflicting perceptual cues, visual as well as aural. Even without any visual aspect close sound sources seem 'bigger'. Aural perspective is not the same as visual perspective, though there are some similarities. Visual distance acuity is probably not much better than aural distance acuity. Both rely on comparison, experience and supposition. My hunch, which I cannot back up with formal theory, is that distance perception is relative rather than absolute. So, I would expect the two 'rooms' to sound broadly similar though not identical, assuming 'proper acoustic characteristics' and appropriate NFC. Distance perception would be consistent, though different, in each 'room'. Apart from widening the listening sweet spot, are larger rooms better at reproducing distance cues when using the same speaker configuration? It has been said several times on this list that the size of the sweet spot is related to wavelength and not the size of the speaker rig, and I'm not knowledgeable enough to disagree. Certainly larger rooms have later and lower level reflections, with lower frequency resonant nodes and a more even frequency distribution of the harmonics of those nodes. Speakers can be more easily located away from walls and corners, resulting in direct sound sound from them arriving earlier and being louder than reflected sound. Is distance perception directly related to speaker distances? I suspect that that it is related in the case of ambisonics, though not directly. This is more psychoacoustics than just physics or acoustics. Ciao, Dave Hunt ___ 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/20110727/335f0164/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Distance perception (really speaker wire discussion!)
with regard to a passive speaker and a modern, A/B class solid state end stage? I mean, I don't really see cable resistance shifting their operating point much, even with feedback, within the audible range. What is it that I'm missing? I swapped out some lamp cable on the speakers of a stereo setup some years back with some cheap stranded speaker cable I bought at Costco. Each core of the cable was about 3 times the cross sectional area of the lamp cord (each core of the speaker cable was about 3/16 in dia). The distances were not great, 5 or 6 feet. The improvement in stereo imaging was huge. Previously the image had wandered around between the speakers seemingly at random, now it was rock solid at the point wherever it was when I recorded it. ___ 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/20110727/2a25f5c3/attachment.html ___ 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/20110727/bbcdd993/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Distance perception (really speaker wire discussion!)
(unless the amp sits in the sweet spot) but my next rig, in my own house, in bangalore next year, will have same length wires to all the speakers. umashankar i have published my poems. read (or buy) at http://stores.lulu.com/umashankar Date: Tue, 26 Jul 2011 21:57:49 -0700 From: d...@dgvo.net To: sursound@music.vt.edu Subject: Re: [Sursound] Distance perception On 26/07/11 3:41 p.m., Sampo Syreeni wrote: On 2011-07-26, Fons Adriaensen wrote: I certainly don't want you to waste your money on fancy speaker cables. Never thought otherwise. That's obviously never been what we do here. ;) But resistance does matter, so a good cross section such as 2.5 mm^2 puts you on the safe side. What I was trying to ask is, what's the real problem with resistance, especially with regard to a passive speaker and a modern, A/B class solid state end stage? I mean, I don't really see cable resistance shifting their operating point much, even with feedback, within the audible range. What is it that I'm missing? I swapped out some lamp cable on the speakers of a stereo setup some years back with some cheap stranded speaker cable I bought at Costco. Each core of the cable was about 3 times the cross sectional area of the lamp cord (each core of the speaker cable was about 3/16 in dia). The distances were not great, 5 or 6 feet. The improvement in stereo imaging was huge. Previously the image had wandered around between the speakers seemingly at random, now it was rock solid at the point wherever it was when I recorded it. ___ 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/20110727/2a25f5c3/attachment.html ___ 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/20110727/bbcdd993/attachment.html ___ 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/20110727/54bed32c/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - No virus found in this message. Checked by AVG - www.avg.com Version: 10.0.1390 / Virus Database: 1518/3790 - Release Date: 07/26/11 -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20110727/f67c98a2/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Distance perception (really speaker wire discussion!)
: Up to 40 feet : 14AWG 40-60 feet: 12 AWG 60-100 feet: 10 AWG - Neil On Jul 27, 2011, at 8:03 AM, umashankar mantravadi wrote: years ago (no decades ago) i found what a huge difference it made if the wires were reasonably thick, and cut to be exactly same length. cutting them to same length is problematic with eight loudspeakers (unless the amp sits in the sweet spot) but my next rig, in my own house, in bangalore next year, will have same length wires to all the speakers. umashankar i have published my poems. read (or buy) at http://stores.lulu.com/umashankar Date: Tue, 26 Jul 2011 21:57:49 -0700 From: d...@dgvo.net To: sursound@music.vt.edu Subject: Re: [Sursound] Distance perception On 26/07/11 3:41 p.m., Sampo Syreeni wrote: On 2011-07-26, Fons Adriaensen wrote: I certainly don't want you to waste your money on fancy speaker cables. Never thought otherwise. That's obviously never been what we do here. ;) But resistance does matter, so a good cross section such as 2.5 mm^2 puts you on the safe side. What I was trying to ask is, what's the real problem with resistance, especially with regard to a passive speaker and a modern, A/B class solid state end stage? I mean, I don't really see cable resistance shifting their operating point much, even with feedback, within the audible range. What is it that I'm missing? I swapped out some lamp cable on the speakers of a stereo setup some years back with some cheap stranded speaker cable I bought at Costco. Each core of the cable was about 3 times the cross sectional area of the lamp cord (each core of the speaker cable was about 3/16 in dia). The distances were not great, 5 or 6 feet. The improvement in stereo imaging was huge. Previously the image had wandered around between the speakers seemingly at random, now it was rock solid at the point wherever it was when I recorded it. ___ 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/20110727/2a25f5c3/attachment.html ___ 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/20110727/bbcdd993/attachment.html ___ 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/20110727/54bed32c/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - No virus found in this message. Checked by AVG - www.avg.com Version: 10.0.1390 / Virus Database: 1518/3790 - Release Date: 07/26/11 -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20110727/f67c98a2/attachment.html ___ 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/20110727/96c6b373/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Distance perception (really speaker wire discussion!)
Surely a Duracell would be perfect for the job, I mean, it does wonders for that rabbit... The problem with using a cheap battery for doing this is that those electrons which are really not able to move anymore (for example those having a broken leg, the result of smashing into another one going in the opposite direction) are not flushed out, but merely reduced to debris that will impede the flow of the new electrons. To really clean up your cable you need something more sophisticated and expensive, the more expensive the better. -- FA ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - No virus found in this message. Checked by AVG - www.avg.com Version: 10.0.1390 / Virus Database: 1518/3790 - Release Date: 07/26/11 -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20110727/8c30093f/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Distance perception (really speaker wire discussion!)
Am I missing something? You send electrons and the speaker cone moves out, o.k. It comes back by itself. But surely you want it to move _in_ as well? How do you do that without positrons. (I think that's right, most things in surround sound seem counter-intuitive: So I doubt if it is positrons out / electrons in?) Anyway, I've learnt something: I always thought the little arrows on all my speaker cables meant they were made by workers in prisons (or is the arrow as a prison sign non-ISO / ITU?). Michael On Wed, Jul 27, 2011 at 05:52:58PM +0530, umashankar mantravadi wrote: havent you heard of tired electron distortion ? (TID). the electrons in speaker wire get tired moving back and forth and not going anywhere. the solution is to disconnect the speaker every few hours connect a battery one side and short the other, so all the old electrons can be flushed out (i think i read this in the wireless world) umashankar The problem with using a cheap battery for doing this is that those electrons which are really not able to move anymore (for example those having a broken leg, the result of smashing into another one going in the opposite direction) are not flushed out, but merely reduced to debris that will impede the flow of the new electrons. To really clean up your cable you need something more sophisticated and expensive, the more expensive the better. -- FA ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Distance perception (really speaker wire discussion!)
I found this message really intriguing since the rabbit is really in an ad for Energizer batteries not Duracell. One wonders why advertising is useful! I have had exactly the same experience. The ads are memorable, but what they are ads FOR is not. Better than the original--who can forget the old master at the easel. But what was being advertised? It's not nice to fool Mother Nature'. What was that an ad for? I can't believe I ate the whole thing You ate it, Ralph --unforgettable but what was the product? I suppose this is good--the culture is added to without benefit to the probably undeserving! Robert On Wed, 27 Jul 2011, Richard wrote: Surely a Duracell would be perfect for the job, I mean, it does wonders for that rabbit... The problem with using a cheap battery for doing this is that those electrons which are really not able to move anymore (for example those having a broken leg, the result of smashing into another one going in the opposite direction) are not flushed out, but merely reduced to debris that will impede the flow of the new electrons. To really clean up your cable you need something more sophisticated and expensive, the more expensive the better. -- FA ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - No virus found in this message. Checked by AVG - www.avg.com Version: 10.0.1390 / Virus Database: 1518/3790 - Release Date: 07/26/11 -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20110727/8c30093f/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Distance perception
Speaker wiring really is a hot topic on all audio related forums. Next time I'll use the term speaker wire instead of lamp cord. :-) For a small and inefficient Kef satellite speaker (3 with a tiny coaxial tweeter and internal crossover circuit), unable to reproduce frequencies lower that 120Hz, driven by a dirt cheap 10W class-T amp, for listening at a maximum distance of 2.5 meters, I doubt that using short lamp cords will be my worst problem; sleeping well, for example, is a better investment to improve my listening experience than getting better cables or amplified speakers. For lower frequencies I use small subs with integrated amps; I have no idea if Kef used some negative impedance trick in their cheapest sub. Wed, 27 Jul 2011 07:43:37 +, Fons Adriaensen f...@linuxaudio.org a écrit : On Wed, Jul 27, 2011 at 01:41:51AM +0300, Sampo Syreeni wrote: On 2011-07-26, Fons Adriaensen wrote: I certainly don't want you to waste your money on fancy speaker cables. Never thought otherwise. That's obviously never been what we do here. ;) But resistance does matter, so a good cross section such as 2.5 mm^2 puts you on the safe side. What I was trying to ask is, what's the real problem with resistance, especially with regard to a passive speaker and a modern, A/B class solid state end stage? I mean, I don't really see cable resistance shifting their operating point much, even with feedback, within the audible range. What is it that I'm missing? When the voice coil of speaker moves in the magnetic field it is surrounded by it generates a voltage proportional to its velocity. Ideally that voltage should be equal to the one produced by the amplifier: in that case the amplifier has complete control over the movement. You can easily test this: disconnect the speaker and gently push the cone of the woofer. You will see it moves quite easily. Now connect the speaker and switch on the amplifier, OR just short-circuit the speaker terminals. In both cases the speaker sees a very low impedance, and it will resist movement. In practice there is a problem: any resistance in series with the 'ideal' voice coil means that those two voltages are not equal and the amplifier is not fully in control. The resistance that appears in series is the the sum of the DC resistance of the voice coil itself, cable resistance and the output impedance of the amplifier. This sum should be as small as possible, and cable resistance can be a significant part of it. One advantage of integrated amps/speakers is that the amplifier can be designed to compensate for this resistance by giving it a negative impedance. This has to be controlled very carefully - overdoing it makes the whole thing unstable and ready to auto-destruct. Which is why it can't be done with separate amps and speakers. Ciao, ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Distance perception
Wed, 27 Jul 2011 07:53:18 +, Fons Adriaensen f...@linuxaudio.org wrote : On Tue, Jul 26, 2011 at 10:26:49PM -0400, Marc Lavallée wrote: How large is the resulting stereo image? As large as you make it, see below. In your earlier post you mentioned that you can't explain why you like virtual speakers better than using real speakers. Can you describe some perceived differences? For example, how are rendered mono signals; are they right in the middle or smeared between the two virtual speakers? In other words, is localization better when using virtual speakers? Is your technique documented somewhere? Can it work with a horizontal hexagon? With 2rd order AMB? Sure. There isn't much to document, just set up your AMB system and use two AMB panners for the L and R signals. Easy! -- Marc ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Distance perception
On 07/27/2011 04:26 AM, Marc Lavallée wrote: Tue, 26 Jul 2011 21:32:26 +, Fons Adriaensenf...@linuxaudio.org wrote : The thing is that I very much prefer listening to stereo using two virtual speakers panned into 3rd order AMB rather than sending L,R directly to two of the speakers. It's very interesting! How large is the resulting stereo image? Is your technique documented somewhere? as fons said, it's just panning. at lac 2010, i presented a paper on using this technique to play back arbitrary discrete multichannel works on an ambisonic rig, with some listening tests: http://stackingdwarves.net/public_stuff/linux_audio/lac2010/day2_1130_General_purpose_Ambisonic_playback_systems_for_electroacoustic_concerts.ogv executive summary: in the general case, it's very nice. for some signals and some expectations, it does not work that well. but fons' preference for the bastardized stereo sound over native reproduction is not shared by most people i talked to, unless you make the triangle significantly wider than 60°, at which point the wow! effect takes over :) Can it work with a horizontal hexagon? With 2rd order AMB? easily. my own tests were all on 3rd order rigs, but i've done it on a hexagon at home, and it was 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
Re: [Sursound] Distance perception
On Wed, Jul 27, 2011 at 01:19:50PM -0400, Marc Lavallée wrote: In your earlier post you mentioned that you can't explain why you like virtual speakers better than using real speakers. Can you describe some perceived differences? For example, how are rendered mono signals; are they right in the middle or smeared between the two virtual speakers? In other words, is localization better when using virtual speakers? This is very subjective, but yes, I have the impression it is better. Also the speakers tend to disappear as being the sources of the sound and there is less interaction from the room - the sensation that the sound is 'just there' is stronger than for straight stereo. But again, this is quite subjective and may be particular for my setup. If you have the required hardware I'd say: just try it ! Ciao, -- FA ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Distance perception
On 27 Jul 2011, at 18:33, Fons Adriaensen f...@linuxaudio.org wrote: On Wed, Jul 27, 2011 at 01:19:50PM -0400, Marc Lavallée wrote: In your earlier post you mentioned that you can't explain why you like virtual speakers better than using real speakers. Can you describe some perceived differences? For example, how are rendered mono signals; are they right in the middle or smeared between the two virtual speakers? In other words, is localization better when using virtual speakers? This is very subjective, but yes, I have the impression it is better. Also the speakers tend to disappear as being the sources of the sound and there is less interaction from the room - the sensation that the sound is 'just there' is stronger than for straight stereo. But again, this is quite subjective and may be particular for my setup. If you have the required hardware I'd say: just try it ! Do you find it varies with material? People don't always say it this way, but sometimes increased localisation blur is nice! S. Ciao, -- FA ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Distance perception (really speaker wire discussion!)
If you have a suitable LiOn battery pack, shorting the terminals out with the cable perks up most the tired electrons - and the subsequent explosion will remove any that are too far gone... On Jul 27 2011, Sampo Syreeni wrote: On 2011-07-27, umashankar mantravadi wrote: havent you heard of tired electron distortion ? (TID). the electrons in speaker wire get tired moving back and forth and not going anywhere. the solution is to disconnect the speaker every few hours connect a battery one side and short the other, so all the old electrons can be flushed out (i think i read this in the wireless world) Alternatively you can have spare cables, and slowly drain them over night in an upright position. ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Distance perception
On Wed, Jul 27, 2011 at 06:50:03PM +0100, Scott Wilson wrote: Do you find it varies with material? People don't always say it this way, but sometimes increased localisation blur is nice! Good question, but I can't give a definite answer. Most of the material I've been working on there is contemporary (2nd half of 20th century) music for small ensembles, and recorded by myself in a place I know very well. One exception is a concert with madrigals by Adriano Banchieri (late 16th cent.). For that one I could use for the first time (in that place) a suspended ORTF pair, but it was just a bit too far from the stage (practical constraints) and I'm not 100% happy with the result. I'll try to listen to some more diverse material and report my impressions. Ciao, -- FA ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Distance perception (really speaker wire discussion!)
I have been browsing this list long enough to observe that this phenomena only occurs (or at least is only reported, on this list, albeit with annual regularity) in Northern Hemisphere summers. Down under, the summers are so hot that the electrons want to pass through cable as quickly as possible, so they exhibit an exact opposite characteristic: Temporal Intensification Dilation (also DIT, unfortunately); thought to be the caused as them exceeding the speed of light in order to 'get the f*** outa there'. The phenomena can be reversed, or at least alleviated from a 3rd person perspective, by plugging the cables into a live mains socket and biting hard on the other end. David On 28/07/2011, at 3:42 AM, Sampo Syreeni wrote: On 2011-07-27, umashankar mantravadi wrote: havent you heard of tired electron distortion ? (TID). the electrons in speaker wire get tired moving back and forth and not going anywhere. the solution is to disconnect the speaker every few hours connect a battery one side and short the other, so all the old electrons can be flushed out (i think i read this in the wireless world) Alternatively you can have spare cables, and slowly drain them over night in an upright position. -- Sampo Syreeni, aka decoy - de...@iki.fi, http://decoy.iki.fi/front +358-50-5756111, 025E D175 ABE5 027C 9494 EEB0 E090 8BA9 0509 85C2 ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound _ Dr David Worrall Adjunct Research Fellow, Australian National University david.worr...@anu.edu.au Board Member, International Community for Auditory Display Regional Editor, Organised Sound (CUP) IT Projects, Music Council of Australia worrall.avatar.com.au sonification.com.au -- next part -- An HTML attachment was scrubbed... URL: https://mail.music.vt.edu/mailman/private/sursound/attachments/20110728/bffc3272/attachment.html ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
