I should add diffusion can use one channel successfully over several speakers for creative effect - but her eIm talking about the accuracy of panning, point sources etc
On Sun, 25 Oct 2020 at 09:32, Augustine Leudar <augustineleu...@gmail.com> wrote: > Stefan - I think we may be getting crossed wires here (pun not intended) > > Me: *“one channel over several speakers sounds crap”* > " > You: *"* > *I would say your statement is just wrong. We are following normal > panning rules, which are proven in millions of * > *recordings."* > > Stereo recordings have two channels, not one - unless you're referring to > mono which of course can sound fine with one channel on two speakers - but > has no panning whatsoever > But perhaps you are not understanding what I am saying or perhaps you are > trolling me :) You suggest "just trying VBAP - well I first "just tried > VBAP" fifteen years ago and have used it in literally hundreds of > installations since and much prefer it to ambisonics in 90 percent of > situations.- I literally use it for work nearly every day and its cousin > DBAP and other forms of amplitude panning, day in day out so I do hope you > take the time to actually understand what I am trying to say otherwise I > fear this may be wasted time for both of us . > > "*Stereo to 4 speakers: You can’t map stereo to positions which are out > of the stereo front*." > > You can and people do - but it sounds crap - which was my point - people > upmix a stereo file to 5.1 for example in post houses all the time there is > a variety of ways they do this and you can read about them here : > > https://link.springer.com/chapter/10.1007/978-3-642-10546-3_28 > > "*It is important to see that every position is panned to 2 speakers in * > *2D, and (usually) 3 speakers in 3D.*" > ????? Yes and no - stereo is panned to positions in 2 speakers of course > but I would think more carefully about what 2D and 3D actually mean ....... > technically speaking - 3D just refers to 3 dimensions. 3D could refer to a > million speakers, so could 2D actually. It's very rare for any kind of > spatial audio to be rendered over 3 speakers though it happens. Whilst I > know simple surround systems are referred to as 3D In reality the whole > thing is a misnomer, 3D should include height and proximity. So a point > source (1 speaker ) should be called 0D, Stereo should be called 1D - a > line - quad/5.1 octaphonic/3 speakers you refer to should be called 2D as > its just a flat surface- from then on we include height - Ambisonics when > rendered with height, should, in my opinion, should be called 2.5 D as it > cant really create proximity properly - aka sounds coming close to you. > True 3D audio, where a sound can be anywhere in 3D space including sounds > that come right up close to you can only be created by DBAP in my > experience, or other amplitude panning and perhaps binaural (not heard > this convincingly yet) though Matt Montags WFS with height system might be > able to do it. More on the definition of dimensions : > > https://gadgetsthink.com/what-is-dimension-full-explained-1d-2d-3d-4d-etc/ > > You could argue you could add height to 3 (or even 2 or 1) speakers using > psychoacoustic effects , directional bands etc making it 3D - or you could > stick one speaker up a lampost for height - but that's another can of > worms. Recent "developments" in 4D, 8D audio etc etc are just marketing > gimmicks. > > Anyway, - I am not talking about ambisonics or object-based panning (and > yes object-based panning systems such as Atmos use amplitude panning in a > system similar to VBAP but instead of a triangle of speakers uses a > rectangular tesselation : > https://patents.google.com/patent/WO2016210174A1/en) . > I am talking for want of a better expression amplitude panning and also > the Scheoops type system at the beginning of this thread. > Lets me try and explain things as clearly as possible. > IF I have a stereo file in which a bird flies from one speaker to another > and I simply "upmix" this stereo file by doubling it onto a quad array then > the bird will be flying from the front left to the front right speaker AND > the back left to the back right speaker - which willl sound crap, or at > least not usually the desired effect . So in the example of the Scheops > setup - you have 8 hypercardioid speakers point to the 8 corners of the > cube - each one of those channels is meant to go go to ONE speaker of a > cube array. Ie each one of those mics and speakers covers one corner or an > eighth of the 3D sound field. Let's go back to the bird. Say I have a bird > happily staying in the top right speaker of my octaphonic cube as was > recorded there by my mic or positioned there by mu panner. If you > suddenly get that top right corner channel of the octatonic cube and put it > on two speakers instead of just the one it was originally meant to > represent (aka upmixing) then the bird will no longer be an accurate point > source in one place it will now be coming from two places, if those two > speakers are in different trees - that bird will now be coming from two > trees - aka the bird will suddenly be larger, or the imaging blurred and > you might get lucky with precedence effect,this will apply to all panning > in the sound scene too if you have upmixed all speakers, the further apart > the speakers are the worse it will be. For me this kind of thing is > crucially important as I do walkaround installations that cannot have a > "sweet spot". So upmixing presents a problem for this type of 3D audio > recordings - and perhaps less so for ambisonics. Now downmixing with this > kind of recordings and composition actually works quite well and I have > tried it many times when I've needed to send a rough mix to prospective > clients and I am left with the daunting task of downmixing a 28 channel > installation to a stereo file - you have to be very selective about which > channels you use and the perspective of the listener. Funnily enough the > stereo recordings I have downmixed from quad and octaphonic recordings > sound strangely spacious. I hope this makes my point of view clear - it is > quite simple and based on years of experience and research and is quite > practical - things have to work or I don't get gigs and the public response > is not good simple as that. > Delightful as this conversation is I have to get back to work and will be > offline for a bit - I bid you good day sir. > > On Sun, 25 Oct 2020 at 01:34, Stefan Schreiber <st...@mail.telepac.pt> > wrote: > >> >> Stereo to 4 speakers: You can’t map stereo to positions which are out >> of the stereo front. >> >> Octomic to 20 speakers: Should actually (and does) work, via simple >> panning. >> >> It is important to see that every position is panned to 2 speakers in >> 2D, and (usually) 3 speakers in 3D. >> (If speakers should stay empty I don’t see any problem.) >> >> “one channel over several speakers sounds crap” >> >> We are following normal panning rules, which are proven in millions of >> recordings. So I would say your statement is just wrong. >> >> You don’t spread “8 speakers over 20 speakers” in some statistical >> ways, if that is what you meant. >> So I just have suggested to “try” VBAP, obtaining some very reasonable >> (and proven) results. >> >> Object and speaker panning is not very different, by the way. >> (You can see the speakers also as objects. ) >> >> >> Best, >> >> Stefan >> >> >> >> >> >> >> >> ----- Mensagem de Augustine Leudar <augustineleu...@gmail.com> --------- >> Data: Fri, 23 Oct 2020 23:21:50 +0100 >> De: Augustine Leudar <augustineleu...@gmail.com> >> Assunto: Re: [Sursound] Recorder for ORTF-3D OUTDOOR SET >> Para: Surround Sound discussion group <sursound@music.vt.edu> >> >> >> >> > I refer to mapping, for example, a stereo file to 4 speakers, an >> octophonic >> > to 20 speakers etc - one channel over several speakers sounds crap - so, >> > for example, the bird that should be a point source coming out of one >> > speaker is now coming of three menaing th ebird i s no longer a point >> > source etc etc - the same goes for panning so yes horribly blurred - Im >> not >> > talking about objects >> > >> > On Fri, 23 Oct 2020 at 13:44, Stefan Schreiber <st...@mail.telepac.pt> >> > wrote: >> > >> >> >> >> You < can > remap stereophonic recordings, via simple panning. >> >> >> >> Are audio objects “horribly blurred” if you render them? Don’t think >> >> so... ;-) >> >> >> >> Best, >> >> >> >> Stefan >> >> >> >> >> >> >> >> >> >> >> >> >> >> ----- Mensagem de Augustine Leudar <augustineleu...@gmail.com> >> --------- >> >> Data: Fri, 23 Oct 2020 12:33:34 +0100 >> >> De: Augustine Leudar <augustineleu...@gmail.com> >> >> Assunto: Re: [Sursound] Recorder for ORTF-3D OUTDOOR SET >> >> Para: Surround Sound discussion group <sursound@music.vt.edu> >> >> >> >> >> >> >> >> > you can also get reasonably nice downmixes to quad and stereo by >> >> combining >> >> > channels as well . However, the problem with Scheops type systemsI >> see is >> >> > upmixing rather than downmixing. YOur basically spreadinge signal >> over >> >> > several speakers when you do that which blurs localisation horrible- >> and >> >> > this is where ambisonics should, theoretically, have an advantage. >> >> > >> >> > < >> >> >> https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail&utm_term=icon >> >> > >> >> > Virus-free. >> >> > www.avast.com >> >> > < >> >> >> https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail&utm_term=link >> >> > >> >> > <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2> >> >> > >> >> > On Thu, 22 Oct 2020 at 16:32, Fons Adriaensen <f...@linuxaudio.org> >> >> wrote: >> >> > >> >> >> On Thu, Oct 22, 2020 at 12:36:38PM +0100, jack reynolds wrote: >> >> >> >> >> >> > The only problem with using ambisonics mics is the high frequency >> >> limit >> >> >> > above which they stop working properly. A second order ambi mic >> >> reduces >> >> >> > this problem, but above about 7Khz the not quite coincident >> capsules >> >> >> > becomes a problem. >> >> >> >> >> >> First order responses from an OctoMic are near perfect up to 11 kHz >> or >> >> so, >> >> >> and not perfect but still very usable even at 15 kHz. I doubt very >> much >> >> >> if there is any 'real' cardioid' doing better at that frequency and >> >> above. >> >> >> Certainly not if you take diffraction / reflection from the mic >> body and >> >> >> clamp into account. >> >> >> >> >> >> Anyway, have you ever considered the sort of frequency and polar >> >> response >> >> >> you get by combining signals from capsules spaced more than 10 cm >> apart >> >> ? >> >> >> You'll find they look quite horrible if you care to compute or >> measure >> >> >> them. >> >> >> >> >> >> You could of course object that those should never be combined, just >> >> each >> >> >> one sent to its own speaker. But that would mean that such a one to >> one >> >> >> mapping is the only possible way to use such signals if you want to >> >> >> preserve >> >> >> sound quality. No downmixing or anything similar (e.g. binaural) >> >> allowed. >> >> >> >> >> >> But we all know that this is not true, we all have heard very nice >> music >> >> >> recordings done with spaced mics. Even those in theory horrible >> >> frequency >> >> >> or polar responses resulting from spaced mics can sound quite well. >> Wich >> >> >> in turn means that this whole 'imperfect polar responses' debate is >> >> mostly >> >> >> academic if not irrelevant. >> >> >> >> >> >> >> >> >> Ciao, >> >> >> >> >> >> -- >> >> >> FA >> >> >> >> >> >> _______________________________________________ >> >> >> 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. >> >> >> >> >> > >> >> > >> >> > -- >> >> > Artist website: www.augustineleudar.com >> >> > Business website: www.magikdoor.net >> >> > -------------- next part -------------- >> >> > An HTML attachment was scrubbed... >> >> > URL: >> >> > < >> >> >> https://mail.music.vt.edu/mailman/private/sursound/attachments/20201023/17717069/attachment.htm >> >> > >> >> > _______________________________________________ >> >> > 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. >> >> ----- Fim da mensagem de Augustine Leudar <augustineleu...@gmail.com> >> >> ----- >> >> >> >> >> >> >> >> _______________________________________________ >> >> 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. >> >> >> > >> > >> > -- >> > Artist website: www.augustineleudar.com >> > Business website: www.magikdoor.net >> > -------------- next part -------------- >> > An HTML attachment was scrubbed... >> > URL: >> > < >> https://mail.music.vt.edu/mailman/private/sursound/attachments/20201023/c1b3c891/attachment.htm >> > >> > _______________________________________________ >> > 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. >> ----- Fim da mensagem de Augustine Leudar <augustineleu...@gmail.com> >> ----- >> >> >> >> _______________________________________________ >> 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. >> > > > -- > Artist website: www.augustineleudar.com > Business website: www.magikdoor.net > > > -- Artist website: www.augustineleudar.com Business website: www.magikdoor.net -------------- next part -------------- An HTML attachment was scrubbed... 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