Re: [LAD] A Cathedral in your backyard

Jens M Andreasen wrote: no. i said that "classic" ambisonics decoders do it, and it leads to problems in large auditoriums with listeners outside the sweet spot. take a stereo rig: you can put a source "outside" the speakers by adding antiphase sound to the opposite one. impressive, but works only if you're in the middle. close to the antiphase speaker, the image collapses into that speaker. imagine you are standing off-center. all speakers start playing. two problems: one, if the auditorium is large, the speakers close to you might hit a lot earlier than those on the opposite side. if they are more than about 30ms apart, the haas effect kicks in and you will localize the sound as coming from the closer speakers. two, if the levels of the far and close speakers differ by more than 6-8 db, you will localize the sound at the louder source even without the haas effect. not so much an issue, because such arrays carry a long way and the level does not drop much. origo? yes. reversed. i'm not an expert on this, but my guess is that when you try such things, you have to take into account that it is *not* a standing wave field. it travels, but in the wrong direction. that means your ITD cues (interaural timing difference) will be wrong. i guess projecting virtual sound sources inside an auditorium is akin to making things invisible according to douglas adams: in almost all cases, it's more convenient to actually put a real sound source there :) -- jörn nettingsmeier home://germany/45128 essen/lortzingstr. 11/ http://spunk.dnsalias.org phone://+49/201/491621 Kurt is up in Heaven now.