[sdiy] tanh distortion in a filter

[Neil Johnson]

Hi Tom,

> Can I just ask if there's anything particularly special about tanh in this
> situation?
>
> It seems to me that you could use pretty much any sigmoid function.

Errr.... no.  Read Achim's paper that Andrew linked to:

A. Gratz, Operational Transconductance Amplifiers
http://synth.stromeko.net/diy/OTA.pdf

Explains all the maths and *why* tanh.

Cheers,
Neil
-- 
http://www.njohnson.co.uk