[sdiy] Notch Filter for Logon's Human-Capacitor Filter

[Aaron Lanterman]

On Thu, 14 Dec 2006, Don Tillman wrote:

> Hey Logan, Aaron,
>
> Are you using hand capacitance to directly filter audio frequencies?
> That's doomed... the capacitance is so small you need an impractically
> high impedance to tune it to audio, and that's going to be extra
> susceptable to all sorts of background noise.
>
> Maybe in a Faraday cage, but that's gonna drastically limit musical
> performance possibilities.

I can see performance art piece coming on...

> The filter works, it's a classic.  But the notch is *really* steep and
> *really* narrow, so all your simulation parameters have to be
> specially tweaked to have any hope of catching it.
>
> If you use this filter, fine tuning it is going to be critical and
> very difficult.  And when it drifts a little, it will no longer be
> filter out the 60Hz.

Logon - based on this feedback, I'd say go ahead and let the sucker hum. 
Electric guitarists have been humming for years. Call it a feature, not a 
bug. :)

- Aaron

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