Hi kuro,
While combing effects are easily heard using a pink-noise test signal (and are measureable), they are not significant or audible with music or soundtrack playback.
Moreoever, any speaker or two speakers produce comb-filtering effects. Try it with one speaker and pink noise. As you move your head slightly to one side or the other--only a few inches are necessary-- the arrival times of sounds to each of your ears change as your head changes position and the distance from the speaker driver to each ear changes, resulting in audible comb-filtering effects. You'll hear the high-frequency content alternately increase and decrease because of cancellation and reinforcement.
The notion of time-coherency when put to the test under controlled listening conditions is a lot of high-end blather not based on scientifically controlled listening tests.
It simply doesn't matter with music or soundtrack playback. If we were all ultra-sensitive to combing effects with musical playback from loudspeakers, we'd all be complaining. It would be intolerable.
Regards,
