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Subject: Re: [motm] What is Unity Gain?

From: "Paul Schreiber" <synth1@...>
Date: 2009-02-27

>
> i thought MOTM modules were pretty ironclad ... could you use an MOTM
> multiple as a mixer?

a) Unity gain means a gain of 1 (unity) or no ∗overall∗ gain. Now, in
electronics the term is ∗context sensitive∗.

- a "unity gain mixer" means if I add 4 1 volt signals, I get 4 volts out
(1+1+1+1)

- a "unity gain stage" is also called a "buffer" has a gain of 1. so if I
put in 3V I get out 3V.

b) by ∗definition∗, a multiple has no circuitry, it is just jacks wired in
parallel. If you plug 2 outputs into a mult, there will be ∗some∗ "mixed"
signals, that will depend on what the output impedances of the 2 driving
circuits are with respect to each other AND assuming there is an input also
plugged in, the input impedance of THAT. Adding more inputs or outputs will
∗drastically∗ change the resulting signal.

This is NOT a recommended thing to do. That is why MOTM modules have
built-in CV and audio mixers in them.

Paul S>