8-channel matrix panning

[Lawrence Casserley]

In message <36C8F5E3.7CF22D10 at towson.edu>, Bill Kleinsasasser
<bill at towson.edu> writes
>Hello,
>
>Can anyone point me to information on calculating the dynamic placement of sound
>within an 8-channel speaker matrix?  The speakers would be set in a evenly-
>spaced
>circle around the listening space and I'd like to be able to dynamically and
>arbitrarily move sounds within this space using the matrix calculations to 
>control
>routing to the 8 outputs.  I'd also like to be able to place stereo input in 
>this
>space maintaining and distorting the original spread image within the 8-
>channels.
>
>Any help is greatly appreciated.
>
>Bill Kleinsasser
>
The simplest and most elegant way is to use ambisonic technique. For a
two dimensional array you need only three components; X, Y and W (the Z
[vertical] component is only used in three dimensions.

It is very easy to generate these components and also to decode them for
any number of speakers. I have implemented them on ISPW, so they should
be easy in pd. All the formulae can be found in:

Malham and Myatt, 3-D Sound Spatialisation using Ambisonic Techniques,
CMJ Vol 19 No 4, Winter 1995

Best

Lawrence Casserley

-- 
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