Moog Music Forum

Hi Everyone!

I'm having a tuning issue on my Voyager, hoping someone can help me diagnose the problem. (I have reached out to tech support but thought I would post in the meantime)

I have found the tuning to be fairly unstable, summary of what I'm seeing:

-Warm up time is usually 60-90 minutes for Oscillators to stabilize
-Then I can fine tune Osc 1 to pitch (note every time I start up I have to adjust fine tuning, it's never consistent from one boot up to another)
-For Osc 2 and 3 I use the frequency knob to tune up to where Osc 1 is
-Often tuning will fall out while I'm playing or sequencing the Voyager
-Sometimes the Oscillators will just start randomly wandering (see video link)
-https://drive.google.com/drive/u/0/fold ... JfKNlgLG

My concern is why the Oscillators are still drifting/wandering after a good warm up and tune. Any insight on what could be going wrong here? Temperature in my room is pretty stable. I live in Toronto Canada.

Thanks a million

I only need a warm up of 15-30 mins here.

-Often tuning will fall out while I'm playing or sequencing the Voyager

Using CV or MIDI?

No problems here using MIDI.

-Sometimes the Oscillators will just start randomly wandering (see video link)

Never happened here.
You got other analog synth in your studio? Are they behaving well? Or is there a voltage fluctuation at you home?
I would check also the Voyager PSU. If there are problems there, the tune will not stay perfect at all.

That's how my Voyager RME was behaving.

My Voyager SE has been rock solid.

So I popped the hood on both and compared VCO components. I found that the charging caps in the VCOs (C63, C66, C81)of the RME were incorrect dielectric. If they are the wrong dielectric, the temperature compensation will not work in the expo converter and that makes tuning unstable.

Finding the correct caps was not easy (they must be 3900pf polystyrene caps), I had to buy them overseas in the UK. Once the correct caps were installed, the RME was a lot better.

It's possible that there was a supply issue of the caps and there was a substitution made.