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Gear / Technical Help => Playback Forum => Topic started by: gkatz on February 09, 2011, 01:52:29 PM

Title: 3-D Sound
Post by: gkatz on February 09, 2011, 01:52:29 PM
http://www.theatlantic.com/magazine/archive/2011/01/what-perfection-sounds-like/8377/

a princeton professor is researching this idea, I bet it sounds great.
pretty interesting points and applications

Quote
“The most tiring part of stereo is the fact that the image spatially doesn’t correspond to anything that you ordinarily hear,” Choueiri tells me. “That’s what drove me to create this thing. Your brain is getting the right cues, and you relax. Your brain stops trying to re-create reality.”
Title: Re: 3-D Sound
Post by: Gutbucket on February 09, 2011, 03:00:48 PM
This refers to binaural reproduction over loudspeakers instead of headphones.

Choueiri's primary contribution in this area is improved crosstalk cancellation filter algorithms that aim to eliminate the portion of the output signal from each speaker that would otherwise 'cross-over' and reach the 'wrong' ear on the opposite side of the head. 

His filters and other modern cross-talk reduction systems use two closely spaced speakers placed about 10 degrees apart, which is a big improvement over older style systems that tried to use the traditional stereo 60 degree speaker setup.  The effect only works really well in a narrow sweet spot, or rather a 'sweet line' down the center between the speakers but the narrow speaker placement helps expand that somewhat over the older systems.

If you want to hear what it sounds like, there are free VST plugins that perform cross-talk cancellation using Choueiri's filters and those of others and you can set up a test system using two computer speakers.  There are also hardware boxes that do cancellation.  You can also set up your own simple speaker cross talk cancellation system using a physical barrier in place of the electronic cancellation filter algorithms.  Actually a physical barrier is superior to the electronic filters, but is rather impractical for regular use. You can do so by setting up two speakers on either side of one end of a big piece a plywood and position your head at the other end.  The board keeps the sounds from each speaker separated until they reach your head.  The end result is somewhat like listening to headphones, but without the 'sounds inside your head' issue.  It effectively turns stereo 'inside-out' by placing the speakers directly in front of the listener and forming phantom images out toward the sides for stereo material, and even above and behind for good binaural material which matches well with you own ears/HRTF.

If you wan't to know more, I recently posted more info (including photos and external links) in this thread- http://taperssection.com/index.php?topic=142299.msg1835947#msg1835947 (http://taperssection.com/index.php?topic=142299.msg1835947#msg1835947)
Title: Re: 3-D Sound
Post by: gkatz on February 09, 2011, 05:41:10 PM
cool! thanks for the extensive info on this