Direct MIDI Control of MC-202 by hijacking the internal D/A

[Andrew Schrock]

On Thu, 25 Jun 1998, Sean Costello wrote:
> Thanks to all who have written me on this topic.  From the responses I
> have received, I realize I need to clarify what I am describing.  I am
> also posting this to Synth-DIY - it started as a question on AH.

Ok, I'll keep synth-diy in the CC path as long as it sticks to the topic
of hardware modification. 

> DIN Sync Advantages - can use Sync Out jacks to run other x0x boxes; can
> use Ext. Synth Outs of 202 to control another synth.
> DIN Sync Disadvantages - requires a MIDI/Sync convertor; new sequences
> must be loaded for each song (this takes a long time, and is kind of a
> touchy process).

Check out 202hack: a reverse-engineered java program which inputs 
sequences from a midi file and outputs a .wav file which you can play into
your 202's tape in port. Apologies, I don't have the website on hand, but
I know there's a link from www.synthzone.com in the roland section. 

> MIDI/CV Advantages - allows for unlimited MIDI sequences to control 202
> without reloading sequences; portamento and accent can be programmed
> into these MIDI sequences also.

Maybe. I'm not sure that portamento and accent _can_ be controlled
remotely, at least with most commercial options. I believe that both
features are added between the digital sequencer section and the analog
section, thus a c/v and gate in wouldn't get any functionality. 

> I guess the main reason I would want such a project is just the
> convenience of it all.  Having an MC-202 that ran directly off MIDI, and
> could output 2 seperate CV/Gate channels, plus DIN Sync, would be a very
> compact solution to the problems I am encountering with my live setup.
> Running the MC-202 directly off of an MMT-8 would be great; running an
> SH-101 and TR-606 from that same MC-202 would be even better.

I've been debating this as well... Frankly there just isn't enough space
inside the 202 for the internal midi->cv to be accomplished. (maybe if you
removed the sequencing/digital board, but that would be a real shame)
Blacet Research has a midi->din24 sync chip which (+ a few discretes)
would _probably_ fit inside. I was seriously considering changing 1 of the
sync outs to a midi in, putting this mod in, and thus having an automatic
internal midi sync. This option also has the nice feature of not ripping
up your mc-202's case at all, and is VERY VERY easy to do. (2 resistors, 2
caps and a xtal are all the other hardware you need, i think.. check
metro.net/blacet/music.html) 

I'll repeat myself: With the addition of a midi->cv you would loose the
accent and portamento unless you were careful. These are the two features
that make the 202 sound so cool! Without them I think you'll find yourself
struggling for expressive possibilities... since it has no rand mod, you
can't just stick that on the filter and have a nice burbly trance line
like you can on the 101. 

> I also believe that such a modification could be done with even greater
> ease on an SH-101.  However, I wouldn't know how to do it, and I would
> be concerned that such a modification would interfere with the actual
> playing of the SH-101 as a keyboard instrument.  But maybe it is
> possible.

Hmmm... an sh-101 is a different beast entirely. More space in the case
(well, compared to the 202 at least) and more importantly LESS incentive
to use din24 sync since, well, there isn't any! The sequencer sucks
compared to the 202's, altho it's significantly easier to use. 

So IMO, do a midi->cv fit on the 101 and a din24 sync fit on the 202. How,
you ask? Paia makes a nice midi->cv unit, and there are also several
kenton boxes out there. (www.paia.com and www.synthtech.com respectively
for more info) An external unit is probably your best option. 

Remember, enterprising 202 people: you can also sync the 202 with a tape
click track! (like that output from an mmt-8 and many drum machines) You
may have all you need to sync right now! (you mentioned using an mmt-8
before.. you could do a live acid/techno performance with just the 202, an
mmt-8, and a sampler.) 

I also want to create "all notes portamento" and "all notes accent" 
switches on my 202 like the similar options on the borg-modded 303. (thus
when you really want to get crazy with the sound you can have every note
accent or slide.. handy for live performance.) I'll let people know when 
I'm sucessful with this. 

OBsynthRamble: I have recently acquired a 101 and a 202, the former at a
flea market for $100 last weekend. (had to replace the 3340 tho) Yeah, i
know, it wasn't _that_ cheap, but it's worth bragging about, especially
since nobody's selling them lately. I have to put my 2 cents in tho: they
are very different machines. the 101 is dirty, easy to use, and has nice
modulation options. The 202 is more tedious, hard to program, and doesn't
have as wide a range of sounds. The 101 seems to be more a 
trance/IDM/funky percussive box and the 202 a straight up acid/ambient
box. All IMO. 

Andrew

| Andrew Schrock							|
| Network Programmer, Synthesizer and electronic music enthusiast	|
| aschrock at cs.brandeis.edu						|