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DC-coupling MOTM120

2007-02-10 by gregorykjar

Hi

Recently I got the 120 sub mux and this is a nice module for a lot of things. But the other 
night I tried to feed it 2 LFO squares and then feed the output of the 120 to the 1V/oct input 
of my 300 VCO. Interesting patterns. But it wasn�t a stepped sequence as I expected and it 
turns out the 120 is AC coupled. (you don�t get sustained notes, but note glitches) I know 
Paul has made the AC coupling with a reason but would it be possible to bypass the AC 
coupling capacitor? As far as I can see from the schematic its only C7 between the summing 
opamp and the output opamp. Would such a DC coupling cause instability, DC-drift etc. The 
DC coupling could make all kind of nice selfgenerating sequences. (and it would be easy to 
make a switch to switch between the two modes). Whats do you say Paul (or anybody) can I 
do this without harming the circuits? Or would I get problems. A little bit of DC-offset wouldn
�t be a problem.

Greetings from Denmark

Gregory

Re: [motm] DC-coupling MOTM120

2007-02-10 by Paul Schreiber

There is not a problem with shorting across the AC coupling cap.

Paul S.

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----- Original Message ----- 
From: "gregorykjar" <g@...>
To: <motm@yahoogroups.com>
Sent: Saturday, February 10, 2007 4:10 AM
Subject: [motm] DC-coupling MOTM120

Hi

Recently I got the 120 sub mux and this is a nice module for a lot of things. 
But the other
night I tried to feed it 2 LFO squares and then feed the output of the 120 to 
the 1V/oct input
of my 300 VCO. Interesting patterns. But it wasn\ufffdt a stepped sequence as I 
expected and it
turns out the 120 is AC coupled. (you don\ufffdt get sustained notes, but note 
glitches) I know
Paul has made the AC coupling with a reason but would it be possible to bypass 
the AC
coupling capacitor? As far as I can see from the schematic its only C7 between 
the summing
opamp and the output opamp. Would such a DC coupling cause instability, DC-drift 
etc. The
DC coupling could make all kind of nice selfgenerating sequences. (and it would 
be easy to
make a switch to switch between the two modes). Whats do you say Paul (or 
anybody) can I
do this without harming the circuits? Or would I get problems. A little bit of 
DC-offset wouldn
\ufffdt be a problem.

Greetings from Denmark

Gregory

Yahoo! Groups Links

Re: [motm] DC-coupling MOTM120

2007-02-10 by Scott Juskiw

Yes, you can DC-couple the output with no problems:

http://www.tellun.com/motm/diy/db120/DB-120.html

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>Paul has made the AC coupling with a reason but would it be possible 
>to bypass the AC coupling capacitor?
>