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Subject: RE: [motm] Purchasing decisions

From: "Tkacs, Ken" <ken.tkacs@...>
Date: 2000-04-04

Well, here's my personal take on your question.

I have three 800 EGs and three 300 VCOs to start with, and one of everything
else so far (on order at least). I find those to be the most useful modules
to duplicate for starters. The VCOs because you need to specify initial
harmonic content using VCOs, and the EGs because there are so many
parameters of a sound that are good to control with different contours over
the sound's "life."

There are plans for a new VCO and a new Dual VCA in the near future. I would
consider the VCA to be the next most useful module to have a lot of, because
they not only control the sound's output envelope, but can essentially
control the flow of any signal or control voltage as it travels through your

I calibrated three of the 300 VCOs and one VCF for V/Oct in under thirty
minutes. The first ten of those minutes was spent letting the modules warm
up! I used a MIDI keyboard, a MIDI-CV converter (Encore Expressionist), and
a $99 DVM with a frequency counter in it. I also used the Patch Panel
module-I bought red & black banana posts from Radio Shack and stuck them in
one row of the patch module, to which I clamped the DVM leads, and then took
a patchcord out of that row into the pulse output of the VCO being
calibrated, making sure PWM was off and Width was 50%, just for good

Then I played a low C on the keyboard, tuned the VCO to 100 Hz with the
front panel controls, played a C an octave up, and turned the trim pot until
the DVM frequency counter reading was halfway between what it was and 200
Hz. Then I played the low C again, retuning with the front panel to 100Hz,
then played the C one octave up... going back and forth five or six times.

It doesn't matter that C isn't 100 Hz "for real" because you're just setting
the linearity of the V/Oct converter, and round numbers are easier to work

When that looked stable, I played a C four octaves up and did the same
tweaking until I got 100 Hz at one end of the keyboard and 1600 Hz at the
other. Once that was set, I tried the octaves in between and found rock
solid 200 Hz, 400 Hz, & 800 Hz in between. Calibration done, bring on the
next one.

There is an MOTM Triple Preamp module coming out soon.

-----Original Message-----
From: thudson@... [mailto:thudson@...]
Sent:Tuesday, 04 April, 2000 11:06 AM
Subject:[motm] Purchasing decisions

I've been absent from the MOTM world for a while
but I'm ready to return in full force. I'm going
to put in an order early next week for at least
one of every module that I don't have. I currently
have a 900, 100, 110, and 120. I have a couple of
questions for those with more modules.

- Which modules would you most want duplicates
of? I was thinking of an extra 300, 320, and
800. I know I'll need more VCAs, are there
plans for a VCA other than the 110, or is
there merit in having more than one 110?

- I'm wondering how hard it is to calibrate the
300. I have a low-end scope (Protek 20m dual
trace), but no precision voltage source.
Should I purchase one 300 assembled to use
to calibrate the other?

- I also want to purchase a midi-to-cv. I've
read reviews and I'm leaning towards the
Encore Expressionist. Any opinions?

- I also want to process guitar and other
instruments with my MOTM modules. What
do most of you use to get the right
levels. How far off is +4db/-20db
(my JMP-1 preamp output levels) from
what MOTM wants? Is there a MOTM preamp

Thomas, Eagerly awaiting MOTM heaven...