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Subject: Re: [motm] frustrated beyond belief

From: "Paul Schreiber" <synth1@...>
Date: 2000-03-09

You can't, in general, run audio into the GATE. What you need is something
external
to generate a GATE. There are 2 ways to do this:

a) use a keyboard or MIDI-CV with GATE out. It doesn't matter which key you
press :)

b) use a circuit called an Envelope Follower/Gate Extractor. The EF is a
rectifier followed by a
low-pass filter. This generates a DC level based on the input amplitude.
Then, a comparator is set
to be HIGH (ie at +5V) if this level exceeds a certain trip point (usually a
panel knob).

There will be a MOTM module that does this in about 8 weeks. There are
schematics at

www.synthfool.com/diy

for this as well. I think the old Polyfusion EF is there.

What's wrong with the '120??!

Paul S.

----- Original Message -----
From: mark scetta <n0nspaz@...>
To: <motm@onelist.com>
Sent: Wednesday, March 08, 2000 11:11 PM
Subject: [motm] frustrated beyond belief


> From: mark scetta <n0nspaz@...>
>
> i am having the hardest time doing something that i think should be very
> simple: applying an ADSR to the volume of an audio signal. somebody,
> please, where am i going wrong:
>
> audio in is going to a preamp then into a mult block in my patchbay then
> to the 110VCA and
> gate in on my (older, gate-modified) 800EG
>
> and of course + out of the EG is going to the CV on the 110 and GAIN is in
> the 'bias region' with the CV pot maxxed.
>
> i just need to shape the volume envelope of a signal.
>