Re: [Sursound] Construction of purpose built ambisonic studio.
Steve, I'm not sure I follow everything you're saying about angle errors, but there are a few installations that work well here in the SF Bay area that I have personal experience with. The Listening Room at Stanford's CCRMA is a 3rd-order periphonic facility, described here https://ccrma.stanford.edu/room-guides/listening-room/ The others are in private homes, so I'll let the owners to chime in if they please. They're good sounding rooms, but without special acoustic treatment. (unlike my living room, which is glass on three sides). There are several accounts of Ambisonic reproduction not working well in very dead rooms, such as an anechoic chamber. Also, for 3rd order periphonic you need to place a number of speakers below the listener, which can be a challenge. The acoustically transparent floor in CCRMA's Listening Room is one solution.Eric Benjamin and I have a paper in the upcoming Linux Audio Conference on designing HOA decoders for partial coverage speaker arrays, such as domes and rings. Aaron (hel...@ai.sri.com) Menlo Park, CA US -- next part -- An HTML attachment was scrubbed... URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20140308/a123ed5c/attachment.html> ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] [ot] 4 D sound (!)
On Sun, Mar 09, 2014 at 12:35:34AM +0200, Sampo Syreeni wrote: > There are four basic forms of the theory used in signal processing, > which are all connected but also subtly different. The Fourier > transform is continuous time and continuous frequency. The Fourier > series is periodic time and discrete frequency. The discrete time > Fourier transform is discrete time and periodic frequency. And > finally the discrete Fourier transform is both discrete and periodic > in both frequency and in time. There are just two, the FT and the DFT. The only difference between the last three forms you mention is only a matter of interpretation. Usually a discrete spectrum is interpreted as the exact spectrum of a periodic waveform. But it's equally valid to say its the sampled spectrum of a finite time signal. A discrete representation in the time domain (i.e. samples) is usually interpreted as a finite-bandwidth signal (which is the dual of the second interpretation above), but it's equally valid to say it's the exact representation of a signal that is periodic in the frequency domain (the dual of the first interpretation above). 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] 4 D sound (!)
On 2014-03-09, Fons Adriaensen wrote: I'm not too sure that is a good thing. I'm not too sure it's true. Nor should you be. So do try it out. You do have the equipment, the space, and perhaps even the research funding. Why not make the anecdote into a hypothesis, and then a full fledge theorem? ;) -- Sampo Syreeni, aka decoy - de...@iki.fi, http://decoy.iki.fi/front +358-40-3255353, 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
Re: [Sursound] 4 D sound (!)
On Sun, Mar 09, 2014 at 02:00:28AM +0200, Sampo Syreeni wrote: > I'm not too sure that is a good thing. I'm not too sure it's true. 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] 4 D sound (!)
On 2014-03-07, Timothy Schmele wrote: A large space coming out of a mono speaker sounds like a large space coming out of a mono speaker. It does. But with a proper mono recording -- instead of just a stereo fold down -- and a proper speaker -- e.g. an omni in a relatively dead room -- even mono can be spectacular. Especially with some practice, like we've all had with the stereo pair and its abject phasing, pulling and whatnot. Few people on this list would willingly go down to mono, given a chance. Of course. But few of us have actually heard professional quality mono playback either. So I'd argue we tend to overestimate the benefits of stereo, especially since for most music out there relies on center panned vocals, melody, drums etc. which mono actually does much more solidly than phantom stereo, because most of the important envelopment cues can be substituted for by a lively room (cf. Ralph Glascal's Ambiophonics work), and because every other system besides mono *too* is an acquired and practiced habit. Just monitor your own reactions when you next hear dialogue coming from a hard center, with the actor on screen actually appearing at the middle. With the right movie and the right theatre, that's pretty much as close you get to proper mono. And it really can be spectacular: at low amplitudes, closing your eyes, it can sometimes sound fully transparent, like there was an actual person there. But then in general you probably won't like it with your eyes open. Why? Because most of us, me included, have already ruined our ears with stereo-the-so-called-solid. The fiction it presents us with by now sounds more normal and lifelike than even the physically more accurate mono dialogue or lead voice. I'm not too sure that is a good thing. -- Sampo Syreeni, aka decoy - de...@iki.fi, http://decoy.iki.fi/front +358-40-3255353, 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
Re: [Sursound] [ot] 4 D sound (!)
On 08/03/2014 22:35, Sampo Syreeni wrote: There are four basic forms of the theory used in signal processing, which are all connected but also subtly different. The Fourier transform is continuous time and continuous frequency. The Fourier series is periodic time and discrete frequency. The discrete time Fourier transform is discrete time and periodic frequency. And finally the discrete Fourier transform is both discrete and periodic in both frequency and in time. It took me *ages* to get that shit right, and all that goes on between them. I was pretty happy then. Then along came you guys, with your spherical surface harmonics and Fourier-Bessel decompositions. Even the cylindrical variety. A math friend of mine pointed out number theoretical transforms and how this all ties in with locally compact Abelian groups. Abstract harmonical analysis. Then even my engineer pals suddenly went crazy with discrete cosine transforms, MDCT, modulated and lapped transforms, time-frequency decompositions, general partitions of unity, overcomplete bases, L^1 norms, projection pursuits... An observation - none of this stuff will actually be cool until it figures in a script for The Big Bang Theory... Richard Dobson ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
[Sursound] [t] 4 D sound (!)
On 2014-03-06, Martin Leese wrote: I always remember one teacher commenting on speech, that you can apply* any standard effect and it is still intelligible, except playing it backwards. Not saying that it couldn't be learnt ... Indeed it can. When I was in high school, many moons ago, there was a brief fad for talking backwards. http://www.youtube.com/watch?v=IIRFkpQHMYw http://www.ted.com/talks/michael_shermer_on_believing_strange_things Just sayin. -- Sampo Syreeni, aka decoy - de...@iki.fi, http://decoy.iki.fi/front +358-40-3255353, 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
[Sursound] [ot] 4 D sound (!)
On 2014-03-05, Aaron Heller wrote: The Fourier basis has a countably infinite number of dimensions. Only if you're talking about the Fourier series or the discrete time Fourier transform. The transform proper is indexed by a continuum. There are four basic forms of the theory used in signal processing, which are all connected but also subtly different. The Fourier transform is continuous time and continuous frequency. The Fourier series is periodic time and discrete frequency. The discrete time Fourier transform is discrete time and periodic frequency. And finally the discrete Fourier transform is both discrete and periodic in both frequency and in time. It took me *ages* to get that shit right, and all that goes on between them. I was pretty happy then. Then along came you guys, with your spherical surface harmonics and Fourier-Bessel decompositions. Even the cylindrical variety. A math friend of mine pointed out number theoretical transforms and how this all ties in with locally compact Abelian groups. Abstract harmonical analysis. Then even my engineer pals suddenly went crazy with discrete cosine transforms, MDCT, modulated and lapped transforms, time-frequency decompositions, general partitions of unity, overcomplete bases, L^1 norms, projection pursuits... Now I drink. -- Sampo Syreeni, aka decoy - de...@iki.fi, http://decoy.iki.fi/front +358-40-3255353, 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
Re: [Sursound] 4 D sound (!)
On 2014-03-05, seva, soundcurrent mastering wrote: yes i believe Ambisonics (and real life) would be 4D. that is a traditional University definition of time-based media (film, video, sound). Heh, you might argue that mono is 0D, pantophony 1D, and periphony 2D, based on the intrinsic dimensionality of the emitting manifold and/or the minimal parametrization of direction. If you just *have* to add amplitude control -- nowadays of course not a given -- you just got upto 3D. So why on earth do we need four channels for B-format? Well, that's about representation theory and the role of time; if you want to assign a physical interpretation to that, it'd have to do with direction of propagation, and the possibility of standing fields. The sanest way I can think of it'll is to think of mono as 0D, stereo as .5D, pantophony as 1D, periphony as 2D and filling up the whole space with emitters as 2.5D, since it in theory yields unlimited parallax as well. No such thing as 3D audio can exist, because an intrinsically 3D emitter would require a 4+1D space to radiate into. ;) -- Sampo Syreeni, aka decoy - de...@iki.fi, http://decoy.iki.fi/front +358-40-3255353, 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
Re: [Sursound] Construction of purpose built ambisonic studio.
This could be an interesting thread. I hope it keeps growing. ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
