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Subject: Re: [motm] MOTM '440 complete!

From: jwbarlow@...
Date: 2000-04-19

In a message dated 4/18/2000 9:43:50 AM, noise@... writes:

>The
>only problem is that I haven't been able to calibrate it since I don't
>have
>a 1V/oct source.


I bet you can get "pretty close" to calibrating it by putting a meter
(preferably a DMM) on the "right spot" (wherever the initial frequency knob
connects to) and turning it up until it's in a good, low audio range (high
enough that you can tell what pitch it is). Now note the value of pitch and
the value of the voltage. After that, turn the frequency knob up until you
add exactly one volt, then adjust the scale as needed (I guess this is all
pretty obvious). Keep doing it for as many octaves as you can.

For a filter this should be close enough. I've lately found myself not using
the 1V/oct inputs on VCFs, but rather scaling them down to maybe 1.3V/oct
(I'm just guessing here). It seems that this is more "musical (???)" than a
1V/oct -- OK that's a bit harsh. It seems that non-electronic instruments
have a particular range that they resonate in more than others. I've found,
through judicious use of resonance, and scaling, that I can get an
interesting peak register kinda thing happening.

JB