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In live sound it is common to have a left/right sub-speaker configuration, which will produce an strong interference pattern in the audience area based on listener/sub-speaker locations.

If the left/right sub-speakers were decorrelated (phase randomization?) would this help reduce the interference pattern in the audience area? Would the effect be minimal or significant at low frequencies?

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    $\begingroup$ A change in phase would basically just move the interference minima and maxima around. A stereophonic system is a two point acoustic hologram (ideally the two points would be where your ears are, but that's only approximated by Kunstkopf/dummy head stereophony). If you want to properly reconstruct the sound field at more than those two points, then you need more channels. I read about experiments with, I believe, nine channels some twenty years ago and the method was said to sound very good... it's also completely useless because the system would only work in near perfectly absorbing rooms. $\endgroup$ – CuriousOne Mar 9 '16 at 13:18
  • $\begingroup$ @CuriousOne a constant phase factor would change the maxima. decoherence in the wavefield would probably make the pattern disappear $\endgroup$ – Wolpertinger Mar 9 '16 at 13:25
  • $\begingroup$ The definitive answer will probably be found here: dsp.stackexchange.com $\endgroup$ – user56903 Mar 9 '16 at 13:31
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    $\begingroup$ @Numrok: I don't know what you mean by "decoherence". A phase change is a simple delay. You can do one for each frequency, which moves the maxima and minima around differently for different frequencies. If you want to make this time dependent, or if you are listening to material that has smooth frequency changes (like most music...), then you will get audible phasing and flanging effects. Great as a musical effect, completely useless for improving stereophony. $\endgroup$ – CuriousOne Mar 9 '16 at 13:33
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    $\begingroup$ Phasing is extremely audible. Dolby has patents on these things, by the way. Dolby encoded material also sounds like shredded dung made into a hamburger would taste like. If you want to get good stereophonic results, get yourself a pair of Stax electrostatic headphones and forget about DSP magic. Absolutely nothing that I have heard so far measures up to those babies and they are the correct physical solution to the interference problem. $\endgroup$ – CuriousOne Mar 9 '16 at 14:13

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