thankyou Xavier ... I guess that one of the things that surprises me is that the old rule of "first wave to impact determine the apparent direction" is not at play here, at least not for sound images between speakers and perhaps not at all.
I can create a mental picture where some 300 small waves travels across my bathtub to finally join at the center, creating a splosh as if I just dropped my soap just there ... and then travels back to only create a small swell along the sides more ore less equivalent to the original set of 300 waves ... Hey, say we put that quiet conversation about illegal substances in the center - at origo - wouldn't that mean that all speakers would have to work together in phase as if it was a single one channel mono system? Superimpose 300 distinct random noises on top of that to give the impression that those guys indeed intended to keep their conversation private ... I think their signal at origo should then be approx -30db below average sound level? Lipreading not being allowed. Then there wouldn't be a single point in the room where one could accidentally overhear the conversation except for in a location near the center of the room. Although the signal would be present all over the place, it would fall below hearing treshold. - - - Am I closing in now to an explanation of how this works? I also came to think about how one can have whispering conversations across places build as huge perfect domes without bystanders having a clue about what is going on. The sum of the reflections from the dome would then be kind of equivalent to the sum of the 300 speakers. (To do this experiment at home, it is of course an advantage if you happen to be the Pope and have the Peter Church in your backyard.) mvh // Jens M Andreasen On Fri, 2007-04-20 at 22:00 -0700, Xavier Amatriain wrote: > Jens M Andreasen wrote: > > Uhm ... But you said earlier that "you could literally walk in > > between ..." > > > > Is it OK if I get confused now? > > > Where do you see the contradiction? Ok, here is more or less the situation: > > Large room, 297 speakers spread over the four walls at ear-height. > Speakers are one-way > mid-hi and around 4 subs are in charge of lows (not directional anyway). > > The demo starts. You clearly hear the sound of the band coming from one > side of the > room (and the song... is that actually Miles and John?). You walk in > that direction and > can clearly "hear the position" of each of the players. Uhm, now John is > moving from > left to right in the stage. You get next to the drums, you can feel the > band around you. > > You walk away from the stage and get distracted from the music by the > sound of > clinging glass and melted conversations. To the right a group of girls > laugh way too > loud as you pass by them. You get close to one of the corners of the > room and can > clearly hear two boys discussing where to get the best shit in town... > > And remember, all this with 300 speakers surrounding you on the four > walls ;) > > As a matter of fact I know the people from Iosono (Brandenburg a.k.a. > father of > mp3) are trying to team up with construction companies so speakers are > actually > embedded in living-room walls. We'll see it sooner than we think, I am sure. > > XA > _______________________________________________ > Linux-audio-dev mailing list > [email protected] > http://lists.linuxaudio.org/mailman/listinfo.cgi/linux-audio-dev -- _______________________________________________ Linux-audio-dev mailing list [email protected] http://lists.linuxaudio.org/mailman/listinfo.cgi/linux-audio-dev
