24 db/oct filter schematic

[Jeremy Brookes]

> Anyway, I'm sure that the design you have chosen make the
> resonance peak less narrow. Maybe the best solution would be to
> use four identical capacitors but use two exponential converters,
> each connected to two stages. Then you could voltage control the
> spread of the poles. Might be worth a try, while you're at it.

A similar feature was introduced into the latest OS for my sampler (Yamaha
A3000). They included some new filter types which have two peaks instead of
the usual one and a parameter to alter the spacing as well as the cutoff and
resonance. There are LP and HP versions. It is a useful effect I think, as
you start to get almost formant like effects for vocal type sounds. An
analogue version would be cool.

jezz.

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