Doepfer

Hi All,

reading all these excellent posts on this group made me feel little bit 
guilty that I am not contributing, but only using. So here is little problem 
I resolved a few days ago, and I hope it might help someone:

I purchased recently Roland MPU-101, 4-voice MIDI to CV unit. But in MONO, 
2VOICE, 3VOICE, or 4VOICE mode, there was loud snap at the beggining of 
every note, in certain settings of the filter. I noticed this behaviour on 
both Doepfer and Roland System 100 (!), and it puzzled me a lot (Roland 
converter working pretty bad on Roland synth ). There is also SPECIAL mode, 
that works PERFECTLY! (But I lose 4 voices).

So, my guess was that V-trigger was in range of 10 Volts, and Doepfer 
envelope expects 5V (I don't have System 100 anymore - it got replaced with 
Doepfer A-108). So, I measured output of MPU in different modes, and 
voltmeter had shown range of voltages from 2 to 6. So I was nowhere.

Than I patched gates from MPU into Doepfer A-162 (with 0 settings on A-162). 
Somehow, the spike got tamed, and everything started working perfectly.

So, my assumption is that MPU outputs V-trigger, which is 100 microsecond 
spike of electricity, and not gate, with exception of SPECIAL mode. A-162 
somehow corrects these spikes into gates in its 0 settings, not to mention 
increasing Length knob.

Hope this helps somebody in future, regards

Zoran