Re: [LAD] Attenuation of sounds in 3D space

On Fri, 2010-07-23 at 01:09 +0200, Jörn Nettingsmeier wrote:
> On 07/22/2010 08:42 PM, Ralf Mardorf wrote:
>
> > As an ape (of course I'm an ape like every human is an ape) and troll (I
> > don't see myself as a troll) I suspect phasing too, that's why I
> > overstated argued with the next generation Cochlea-Implant, or needles
> > in the brain.
>
> that is a bogus statement. phasing happens in the brain as well. just
> put on your favourite pair of headphones and wire one side out-of-phase.
> instant nausea. (of course, if you keep it on for a few days, your brain
> will adapt - presto: you'll be hurling all over the real world when you
> finally put them down.)
>
> > Visual 3D, by a surround projection + 3D glasses isn't perfect, but
> > there is just one picture and not several pictures that needs to be
> > phase synced in the eye. Perhaps a week analogy.
>
> a terribly chosen analogy indeed. since when do the eyes care what phase
> an incoming photon is? unless you're staring into a laser, each photon
> will have totally random phase.
> next error: there *are* two images, and they do need to be synced. phase
> is irrelevant, though.

That's the problem with this analogy. We have two eyes and ears, but
most people have better trained eyes, so most people 'see' differences,
but less people 'hear' differences.

>
> > When having 4 or 8 or more speakers I fear phasing at the position of
> > the ears. But perhaps it isn't that much. I'll try to listen to
> > ambisoncs :).
>
> you can get terrible phasing, and not just in the center, but pretty
> much everywhere. that's why some people stagger the timings of the
> loudspeakers a bit, to smear out the phasing until it is more or less
> masked by the content.
> but it should be noted that stereo has the very same problem.

As I mentioned before, it's hard to do a good stereo mix, even when the
speakers are perfectly set up. When you play music on radio, you need to
check the phases of the recordings, because there are a lot of bad
recordings. I guess it becomes harder the more channels you need to
control.

> now if
> method A produces a 60° soundstage with phasing at N units of
> obnoxiousness, a method that produces 360° surround is entitled to 6N
> UoO phasing. in practice, ambisonics does better than this, but there is
> no denying the issue.
> one thing that often gets overlooked: people have learned to accept
> stereo (or, in some circles, 5.1) as the gold standard, and its
> shortcomings have grown into desired features. it's very hard to compete
> with a method that does a few things very well and doesn't even try to
> reproduce most of the auditory cues of, say, a live experience.

Correct, I like stereo, I don't like 5.1 and indeed stereo is very
limited, but with some training it's good to handle.
If ambisonics shouldn't have the disadvantages of 5.1 I might like it.
It's funny, regarding to the German Wiki ambisonics is as old as I'm.

> the main ingredient that makes any sound reproduction system sound good
> is your brain. the trick is to nudge it into sympathy with carefully
> chosen cues.

Btw. I 'try' to do stereo mixes that do sound mono as near as possible
to the stereo mix and mono could be two channels as one or just one of
the two channels. So I limit stereo to a special functionality, but
don't use all capabilities. This could be called 'broadcasting
behaviour'. I know that I need to break this habit for surround sound,
but when listening and unfortunately working with 5.1, I didn't like it.

Btw. even some consumers don't like 5.1, but perhaps because they set up
the speakers completely bad. IIUC they hardly could set up the speakers
completely bad, if they would use ambisonics. IIUC for large rooms there
are many speakers needed, perhaps this is the reason that shit like 5.1,
Dolby surround, Dolby stereo is common. OT: For film on cord Dolby
stereo anyway is nice for stereo, without Dolby there's hardcore wow and
flutter ... hm, regarding to wiki it's called dolby digital, doesn't
matter German filmmakers usually can't pay for Dolby.

Thanx for the information :)

Ralf

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Received on Fri Jul 23 12:15:02 2010