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Subject: RE: [motm] Mixers and CV

From: mark@...
Date: 2001-05-07

>Audio mixers are designed to NOT pass any constant DC signal. When you
>initially applied the CV, you would hear a click and another when you
>removed it.

Right. Audio mixers are "AC coupled" -- they have capacitors at their
inputs.

>You probably would not damage anything EXCEPT if you had some speakers
>attached. The 5-10 volts of the CV is many many times larger than the
>>usual low-level audio signal

I'm not sure what you mean by low level. 10.96Vpk (or 21.92Vp-p) is only
20dBU. The MIL of most Mackie line inputs is 24dBU, which is over 34V
peak-peak -- less than the MOTM PS. Just do not use the mic inputs.

>It would be otherwise OK to try - just keep the levels down really low.
>Mixers usually cut off around 10-20 Hz so anything higher than this ( a
>>fast LFO ) should go through OK.

I've run the output of the 320 directly into my Mackie with no problems --
even a _slow_ pulse (about 9Vpp) wave merely clicks at each transition
point. I've also come up with some interesting sounds using the UEG
(approximately 0-5V) as an oscillator with no problems.

The only danger is using signals that are beyond the audible range. The
mixer can pass subsonics that can damage your woofers. If you use
nearfields I strongly suggest fusing the bass drivers, even if you are not
using synthesizers.