-----Original Message-----
>>> ... Which one module is a good starting module that is useful and would
complement my Korg MS-10 nicely?
Welcome to our little family!
One thing to be aware of if you are using MOTM to expand an MS-10 is that
the older KORG gate system was the switched gate type, and the MS series
were not 1-volt-per-octave based. So for many modules, you will not be able
to simply stack them on and get easy functionality. In other words, if you
added an MOTM VCO, you would not get the results that you might expect.
Similarly, if you wanted to add an EG, you would need to build a gate
modifier.
You can add modules such as the Triple-Resonant Filter without difficulty
because this isn't [necessarily] reliant on the MS-10's gate or keyboard CV.
The sub-octave multiplexer might fatten up that single oscillator without
being dependant on any keyboard CV.
You could actually use any of the MOTM filters; just don't expect to make
the cutoff frequency track the keyboard. Although on the MS-10, that doesn't
even work INTERNALLY, at least not on MINE. I always suspected that the
filter in that thing was not a linear tracking filter. Or maybe mine's just
busted...?
Korg saw which way the wind was blowing and eventually switched over to
voltage gates and 1v/8va pitch CV standards. My Korg MS-10 and Korg MP-4
"Mono/Poly" don't talk to each other, and they were purchased a few short
years apart. The MP-4 does work perfectly with MOTM, although when I first
started using the MP-4 as a voltage source to calibrate my MOTM VCOs I
quickly realized how wildly off the tolerances on the Korg were.
It's not difficult to create a little circuit to modify the gate; it's a
coupe of dollars of parts. Not being an engineer, I would hate to be the one
to advise you on this one, but there are schematics out there and smart
people lurking around here. I think basically you just want to use the Korg
gate to switch on & off a 10v control signal.
If I'm not mistaken, the Korg MS gates are similar to the old Moog Modular
gates, although with a different connector, so you may be able to find a
conversion circuit along those lines. But don't quote me on that; I'm not
that familiar with the Moog.
Larry, would the Pedal Interface do something here...? I haven't built one
yet so I don't know its ins & outs.
The Keyboard CV will be more difficult. It may be the 'deal breaker,'
depending on what you need.
A while ago I considered getting a CV-2-MIDI converter which would
essentially make my MS-10 a MIDI controller, and then use one of the easily
available MIDI-2-CV converters to bring its outputs back to the "real
world," but it's a hassle, expensive, and it's not very easy to find a
decent CV-2-MIDI converter, so I never pursued it.