Issue with Voodoo Labs Analog Chorus

[kfowler8]

I've got an issue with my Analog Chorus perhaps you guys have seen before.

If I power it with a battery is works fine. If I used an external power source I often get a chirping sound. Sometimes it's barely audible and sometimes it's pretty loud. My main power source is a Dunlop DC-Brick but I've also tried using an individual wall wart and had the same issue. it's only this pedal I'm having problems with.

My suspicion is that there's some kind of power filtering issue going on and the chorus effect is causing the noise to chirp.

Got any suggestions?

Thanks,

[M.A.P]

I have the same problem when I run my pedals on a 230V power supply. Most of these are switch-mode power supplies which switch with high frequency (as their name says ). The positive voltage still got the waves from the switching and this is causing the high frequency chirping. You have to smooth the input power but to be honest I don't know exactly how to do this. Maybe a electrolytic capacitor with a high value between positive voltage and ground can help to smooth the input voltage.

Greetings from Germany
Marcus