Doepfer VCO Problem

Hi all,
I realise this might be in the wrong section, and it’s not MI related at all, but I hope you can help.

I’ve just got myself an A-111-1 VCO2 (High End VCO) and it’s massively unstable.
I have four A-110 VCO’s and they’re all great, no problems at all. I also previously had an A-111-1 with no problems at all.

Basically whenever i go anywhere near the module or the audio cable out of it it just goes mental. If i stay completely still and don’t touch anything it’s ok.
I thought it might be a bus board problem, so I tried it on a couple of different boards in my Doepfer Monster Base, but still the same problem. I then removed it completely from the case and put it in a Tiptop HEK, the same problem there too.

I’ve attached an MP3 of it, with just a square wave out with nothing else in the chain. (it does this on all waveforms)
I’m just touching the cable, and not touching the module whatsoever.

I hope you can help.


Solution :wink:

Your “High End” VCO is based on a CEM chip which are somewhat sensitive to bad grounding and static discharges - try using a CEM 3379 Filter board wiht an OLED or Programmer…
In your case i would guess somethig with the Frequency CV in conditioning is broken, have a look at the Jack, maybe its just bad soldering or a piece of debris here.

If this wont work theres nothing you can really do without the schematics expect send it to Dieter… there are “no User servicable Parts” inside

BTW what do you do with 4 Oscillators that only do classical Waveforms???

sounds like some kind of defect.
i would contact dieter doepfer about this, he is usually very helpful.
he won’t receive your email before monday though - yesterday was a holiday over here, and like an estimated 73% of all working germans, he is taking a day off today.

[edit:] woops, fcd beat me to it.

Thanks a lot guys, but after a bit more of a think I’ve decided to send it back to the seller on ebay.
No sense spending any more time on this when I think it might be outside of my comfort zone when it comes to fixing it.

But thanks a lot for your help.


Oh, and fcd72, I’d have one right away if there was anywhere that had them in stock (in EU).
I was waiting until payday to pull the trigger, but missed out on them by a day or so. Gutted.

As for what I do with 4 standard oscillators with standard waveforms…
A bit of everything, from nice melodic stuff to the more esoteric.

Really, no pun indended. I was just curious because i have no 2 the same Oscillatores… well… expect Braidss (whats the Plural of Braids???)

Braidsoxes :slight_smile:

So it will be :wink:


I only have all the same oscillator as I started with an all Doepfer case (that case still is all Doepfer), but am now trying to put together an all MI case (slowly). Which is just going to blow my mind I feel. :slight_smile:

Yay, compared to the DOEPFER Stuff every Module will be a whole new world…

I currently have a eurorackified Anushri plus Grids and Ripples, and am blown away by them. :slight_smile: