[sdiy] filters, state variable in particular

[Roy J. Tellason]

I just happened across a magazine article that among other things talked about 
the state variable filter,  and was wondering how useful that circuit would 
be in the SDIY context.  Comments?

-- 
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space,  a critter that can
be killed but can't be tamed.  --Robert A. Heinlein, "The Puppet Masters"
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Information is more dangerous than cannon to a society ruled by lies. --James 
M Dakin