From eric rehl Sent Tue, Dec 1st 1998, 20:33
I had this same problem with my Pulse +. I had to have a tech build a buffering circuit inside it because otherwise I found it unusable with my 2600 and A100 - tuning would sag the more destinations I patched it to. A blemish on an otherwise fine instrument. earache ---------- >Date: Tue, 1 Dec 1998 14:26:01 +0100 >From: Haible Juergen <xxxxxxx.xxxxxx@xxxx.xxxxxxx.xx> >Subject: AW: Re: [AH] Regelwerk > >> > I've just taken delivery of a Doepfer Regelwerk, and it is a great > >> controller. 8 CV & gate outs! > >> The one thing that bothers me is that if you connect more than one synth >to >> > a CV-out, the voltage drops and the synths cannot be tuned. >> > Does anyone else have this problem? >> > >> Anyone who did this would have this problem ;-) > >You only have this problem when the outputs are either >cheap, badly designed, or simply not intended for >precise V/Oct CV's. (I don't know the circuit of the Regelwerk, >so this is not meant as an offense. I'm trying to give a few >helpful hints *in case* that there is a problem with voltage >droop - for this unit, or for similar output stages. Wheather there is such >a problem with the Regelwerk or not I don't know.) > >> Any synth's CV input is a current drain; the higher the current drain, >> the more the voltage seen at each synth's CV in will sag. >> >> To solve this you can build a simple circuit based around an Op-Amp >buffer. >As someone said before, such a buffer should probably have been built into >the box in the first place. >It's not a question of "designing around physics", as someone posted. It's >part of the price you pay when you buy low budged gear. You don't see things >like this from the outside, nor does it usually appear in the specs. But it >can make a difference. > >JH.