The Cyndustries List

-------------- Original message -------------- 
From: "Doug Wellington" <DougWellington@gmail.com> 
On 2/1/07, krh7c <krh7c@yahoo.com> wrote:
> Hi everyone, I'm new here and to modular analogs.

Welcome to the addiction! ;-)

> I want to put together a modular synth that is a reasonable instrument
> to start and can be evolved and expanded over time.

You can get started with only a few modules. I think I know the
answer to this, but do you want to build a modular that can make
sounds on its own, or do you want to trigger things from a keyboard or
some other controller? (Since you ask about a MIDI converter, I'm
guessing the second one...)

So, you'll need some kind of noise generation device (oscillator -
"VCO") and something to control the volume of the sound (voltage
controlled attenuator - "VCA"). If you want the sound to get louder
and then softer, you'll need an envelope generator ("EG" or "ADSR",
which stands for Attack, Decay, Sustain, Release) to control the VCA.
With a MIDI/CV Gate converter, you'll be able to press a key and
trigger a single note that swells and then fades out. So, with only
four modules, you'll get a basic tone - not a bad start, eh? :-)

I'm guessing that will get old very quickly, so you'll probably want
to add some kind of filter to modify the sound of the VCO. You can
get a manually controlled filter that you twist the knob on, or you
can get a voltage controlled one ("VCF") and get another EG to control
it. There are basically four types of filter, but I'd suggest
starting with a low pass ("LP") one first. If you want to have a
repeating cycle of volume and filter changes, you can use a low
frequency oscillator ("LFO") on either, or both, the VCA and/or VCF
for some fun.

At this point, seven modules or so, you basically have an "analog
monosynth"! :-) After this, you can decide if you want to expand to
more notes (basically just duplicating things - more VCOs, more VCAs,
more EGs) so you can play chords or multiple lines, or you might want
to expand your system to different sound qualities or different ways
to manipulate those sounds. Ask away when you have questions...

One thing I'd suggest is to take a look at the different manufacturers
and decide what format you want to start with. There are three main
sizes - euro rack, frac rack and MOTM, with a couple other formats
used by some manufacturers. Euro and frac rack both use 3U (a "U" is
1.75") high panels, but they aren't really interchangeable.
MOTM-style modules use 5U tall panels. Along with panel size, you'll
also find that knobs and cable connections are smaller and more
closely spaced on euro and frac modules, and larger on MOTM. Don't
worry too much about making a "wrong" decision here - if you decide to
get more than one format, you can get cables with different ends
and/or get a patch panel with the different sizes. Please remember
that modulars can become a "religion" and you'll hear different things
about different formats and different manufacturers. Try to find out
as much as you can before you make the plunge.

Take a look at my web site (listed below) and you'll get a little idea
of what is available. Send me a private email if you want to know
more about my own rig...

Doug

http://www.analognotes.com