How to calibrate/tune?


Since 2 days; I am in Modular World :slight_smile:

Please bear with me.

I have installed doepfer diy synth with tempco with Karl Marx Stadt front panel.

I assume I need to calibrate/tune the vco before I can use with a CV keyboard

Can somebody help me out with the procedure I need follow. ?

Here is the schematics which it shows the trimmers ( P1 , P2 )

First, let the unit warm up. Then you have to apply notes of an octave apart (as it is 1V/octave that would mean CV that are 1V apart e.g. 1V pitch-CV and 2V pitch-CV) and tweak the frequency scale until you get two notes an octave apart. To be sure it tracks well, I would then go ahead and apply notes that are two and three octaves apart (e.g. 1V CV, 3V CV, etc). Once that’s fine, I would tweak the VCO offset so you get a uselful pitch out of it when no pitch CV is applied.
Afterwards I would verify the tracking again.

Isn’t there a manual somewhere?

Thanks @TheSlowGrowth

Yes there is a manual

They mention something about calibration but it is not step by step

Page 6 last Sentence , Page 17 last section.

Is there any go to software or apps for calibration ?

what would you need a software app for?

It’s really as simple as turning the frequency scale trimmer until the notes are correctly spread out. As I said, repeatedly play two notes which are an octave apart (like: C1 and C2) and turn the trimmer until the resulting tones are an octave apart. Once that sounds right to your ears (nothing more is required) you can play C1 and C3 and see if it still fits nicely. Then turn the offset trimmer until you get a useful pitch with no CV connected. Then repeat the first step just to be sure. That’s it.

Basically I’m telling you to do the same as is written in the manual. Have you even tried that? It doesn’t get more “step-by-step” than this.


I told you bear with me :slight_smile:

Thanks for explaning again.