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Subject: Re: [motm] envelope follower

From: Thomas Hudson <thudson@...>
Date: 2000-11-12

On Friday, November 10, 2000, at 10:45 PM, Paul Wagorn wrote:
>
> HOW do I do it with MOTM modules??
>

Envelope follower circuits that I have seen use full wave rectification
with some low pass filtering to reduce ripple. I've done a primitive
EF by plugging the input signal into both X and Y inputs of the
ring modulator and sending this output to a low pass filter.
The output of the low pass filter is roughly the amplitude strength
of the signal. Use this to control a filter cutoff with the original signal
as audio input for the classic autowah. If you also need a gate signal
you can use a 700. The problem being that too little filtering leaves
a ripple, too much gives a sloppy response.

I haven't tried this, but there was a circuit in Electronotes that did
rectification twice, thus raising the frequency by four and
requiring less filtering. Hmm, I've got two 110's here...

Tomy