I've been playing with some of the basic midi functions of the 200e. I kind of gave up on the internal routings (another post perhaps) and set all the modules to Buss A but then decided to more or less ignore that and just throw everything into one 225e fully patchable buss and CV patch everything the old fashioned modular way. I'm happy to say this works and I put together a video demo of me using an Akai MPD16 pad controller to control the 259e and both VCOs in the 261e:
The patch I'm using for this is a simple controller CV->Envelope-> VCA patch with both oscillators of the 261e and the main oscillator of the 259e. I have Buss E on the 255e mapped to midi channel 1 and am running the note on into the 282e gate ins, the pitch out into the CV ins on the oscillators, and to add some spice I'm running the velocity out of the 225e buss into three different sources each with a separate audio track. Velocity on the pads adjusts the volume of channel 1, Envelope attack of channel 2, and Envelope decay of channel 3. I do each sound individually and then mix and match towards the end of the video to give you an idea of what mayhem you can get up to with something as simple as this.
I call this a poor man's touch controller because it obviously is a far cry from something like a Serge TKB or the 200e's own 223e. The pad unit I'm using doesn't offer aftertouch and isn't as responsive as dedicated modular CV controllers. On the other hand it costs about $50 more or less and can be found on any craigslist or guitar center and, even in it's limited way, it opens many doors for real time interactive playing of the 200e.
My experience with midi and the 225e so far is both limited and less than overwhelming. When I used a standard velocity sensitive keyboard and the internal buses and external mapping I experienced slow response to playing notes and a sluggishness in controller CV. It's certainly possible I had something else interfering in the patch (see my previous posts on "hidden" preset settings) but given the emphasis on the computer and midi capabilities of the 200e this was a bit of a let down. I am still trying to figure out why my 250e only sets to buss D despite changes to it's dip switch settings. So far emails to Buchla and various forums haven't given a clue. In the meantime, it felt good to hit something and get some cool sounds. With a bit of work programming the controller and tweaking on the various CV ins on the 200e I'm sure this can sound a lot better and be much more expressive as well.
For now, enjoy the melodic sounds of a demo on percussive noodling.