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[Mikko Helin]

>
>> If you want digital filters look into Hal Chamberlin's
>> book, there's a digital model of state-variable filter,
>> which needs only two or three multiplications/sample.
>
>well what is this model? the book has gone out of print so it's hard to 
>look it from the book. 
>
I think Hal Chamberlin used to sell the photocopies of his
book, his email address is (was?) halc at ycrdi.com
(if he still works for Young Chang Research and Development
Institute). Has anybody ordered his book there?
I have the piece of code for the filter somewhere in my PC
at home, and I'll post it tomorrow.

-Mikko