and of course I mean amplitude panning rather than vbap in that instance - but I have had reasonable results doing the same for full 3D installations as well, at least as resoble as can be expected representing a 3D audio scene in stereo (which is never very good in any format)
On 9 January 2017 at 12:32, Augustine Leudar <augustineleu...@gmail.com> wrote: > Archontis - I mean when I make a multichannel sound installation and use > Vbap to pan it - lets say an eight channel octophonic horizonatal array - > when I export an 8 channel interleaved rendering of this installation later > and play it back on say, Iplayer, it automatically renders it to stereo and > and panning is suprising well represented in stereo. > > On 9 January 2017 at 12:19, Politis Archontis <archontis.poli...@aalto.fi> > wrote: > >> Hi Sampo, >> >> > On 09 Jan 2017, at 06:27, Sampo Syreeni <de...@iki.fi> wrote: >> > >> > The critique I'd have for such panning laws is that they don't really >> respect the ambisonic/Gerzon theory, especially at the low frequencies. In >> essence, they work, and necessarily would *have* to work in the high >> frequency, (ambisonically speaking) high order,sparse array limit. Which is >> why they mostly work for common music and speech signals. >> >> I am a bit baffled by the idea that VBAP is not compatible with >> Ambisonics theory (?) Thinking in terms of velocity and energy vectors, as >> far as I understand, VBAP with the (classic) amplitude panning formulation >> has zero angular error for the (Makita) velocity vectors for all >> directions. If you take the energy formulation of VBAP for high frequencies >> (solving for energies instead of amplitudes) then it results in the maximum >> (Gerzon) energy vectors that the setup can achieve with zero directional >> error again. Of course at low frequencies you cannot achieve the “perfect” >> pressure reconstruction that a mode-matching decoder can achieve, but then >> you see what are the gains that such a decoder imposes on not ideal regular >> setups to realize that perfect reconstruction should be compromised anyway >> with some more practical solution. >> >> >> > However, they fail to work general speaker arrays fully. Especially at >> the lower frequencies. Ambisonically speaking, where we'd go with a >> holistic, whole array, directionally averaged velocity decode. >> >> Again I think it depends how you mean it - VBAP will just work for any >> speaker array with a performance limited by the setup in a quite intuitive >> understandable way (large spread for large triangle apertures, full >> concentration at a speaker direction, nothing for regions outside a partial >> setup etc..). Ambisonic decoding for any array is not designed as easily as >> computing VBAP gains, and it seems for irregular setups, one of the most >> straightforward and practical ways to do it is to combine the properties of >> VBAP and Ambisonic decoding (as the work of Zotter, Batke, and Epain have >> shown). Considering panning specifically, I think it depends on the >> application what works best, for VR or interactive-audio stuff for example, >> where normally sound objects would be rendered with maximum sharpness VBAP >> would work better. If however some and more even directional spreading is >> preferred, then ambisonic panning should be better, or some VBAP variant >> with spreading as has been presented by Ville and others. >> >> So I find Augustine's comments reasonable on panning sounds, but not in >> general: VBAP vs Ambisonics. >> >> > On 09 Jan 2017, at 12:33, Augustine Leudar <augustineleu...@gmail.com> >> wrote: >> > >> > Yes i just mean - when making a 3D sound installation you can use >> various >> > types of panning round a sphere (or whatever of speaker array). You >> seemed >> > to be saying ambisonics had a clear advantage over other types of >> panning >> > for 3D audio - I was just wondering what you saw as ambisonics' >> advantages >> > over VBAP. I've actually found Ambisonics to be worse compared to VBAP >> in >> > many situations and better in others - but generally I use Vbap or Dbap >> . >> > The only real advantage I can see of ambisonics is having one file that >> can >> > be up or down mixed - but you can do that to a degree with Vbap files as >> > well. >> >> (What is a VBAP file?) >> >> That’s if you have actually access to the sound objects with their >> parametric information, in which case sure you can pan them however you >> like, you can even switch between different panners on the fly and pick the >> one you prefer. However, the generality of Ambisonics becomes clear if you >> have real sound-scene recordings, or you don’t have access to the objects >> due to bandwidth limitations, and it makes sense to downmix them to a >> format that preserves their directional properties as good as possible. >> This last case becomes especially important if decoding of some HOA >> channels (or even FOA with parametric decoding) becomes perceptually >> indistinguishable with respect to spatializing many of sound objects >> separately.. >> >> Regards, >> Archontis >> >> _______________________________________________ >> 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. >> > > > > -- > Augustine Leudar > Artistic Director Magik Door LTD > Company Number : NI635217 > Registered 63 Ballycoan rd, > Belfast BT88LL > > -- Augustine Leudar Artistic Director Magik Door LTD Company Number : NI635217 Registered 63 Ballycoan rd, Belfast BT88LL -------------- next part -------------- An HTML attachment was scrubbed... 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