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Subject: Re: [motm] Non standard module uses

From: jwbarlow@...
Date: 2000-08-02

In a message dated 8/1/2000 10:06:24 AM, djthomaswhite@... writes:

>What does a comparator do in a modular patch? Practical uses? Please help
>as
>I am planning to build a "Potpourri" module with a comparator in it and
>I am
>curious of it benefits and techniques required to use it.

One very good use for a comparator is as a gate extractor for an envelope
follower. The EF output goes into the comparator input and the comparators
level is set to an appropriate level for the gate to come on. I point this
out since having no comparator is a very obvious deficiency of the ARP 2600.
As Ken pointed out, it is also the way to generate pulse waves and PWM.

If I'm not mistaken, you can get a very good idea how to build a comparator
module by looking at the CV inputs of the MOTM 700, maybe adding an
additional input on the other input of the comparator IC (an LM311 perhaps).
Comparators are extremely useful when you start getting into more pulse
driven modules (like sequencers and other logic modules).

JB