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Subject: Re: [motm] 120 and 820 playing together

From: "J. Larry Hendry" <jlarryh@...>
Date: 2001-10-04

Just some DIY musings on the subject. Use the delete button if you don;t
care about DIY. :)

If you are interested in taming the tone of a square wave from a frequency
divider, you can do so passively with a capacitor. Certainly, the amount of
taming varies with frequency. So, once might argue about non-linear
function and all sorts of crap reasons why this is not the best way.
However, John Blacet used this concept by putting a capacitor across the
feedback resistor on the output buffer in his frequency divider. He applied
a small value that had little more effect than to knock of the edge, which
was his intention.

Ken Tkacs and I had much discussion about this a lot time ago and he had the
idea to put a selection of caps on a rotary switch so one could dial in the
amount of "low pass filter" desired. So, I did just that. Here is a photo
of my Blacet FD next to my MOTM-120.
http://www.wiseguysynth.com/larry/blacet/blacet_freq_divide.jpg See the 6
position LPF rotary switch ?

I think the passive approach is OK for taking the edge off a square wave.
My 5 caps are sized 1nF, 3.3nF, 6.8nF, 13.3nF, and 26.2nF in this
application. However, there are many ways to skin this cat. I sized my
caps by sound (and what was in my parts box), not calculations. But, I did
find that you roughly have to double the cap size each time to hear a lot of
difference.

Seems like it would be simple enough to make something variable with a pot
and cap in series, but I have never messed with it. I guess my point is
that on a 120, if you wanted an output with some LPF applied, you could
build it in and put another output jack on the 120. so you had both filtered
and unfiltered outputs.

Larry (sorry I can't resist modifying stuff) Hendry


----- Original Message -----
From: bleeped <bleep@...>
To: MOTM list <motm@yahoogroups.com>
Sent: Wednesday, October 03, 2001 5:24 PM
Subject: [motm] 120 and 820 playing together


hello...

i often use my 120 in square/sub mode to distort beats and such... but
turning up subs 3 and 4 basically just outputs a very, very lf square
wave in that situation. i was wondering if anyone does anything similar,
but puts the output through an 820 to get some sort of tone... or less
popping and more beef (or tofu) at least. if you're out there, i'd
appreciate it if you'd let me know what this does!

thanks muchly...

bleep.
out.





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