Doepfer

Hi all,

I'm having some trouble with noise in my system, which I think can be attributed to ground or earth hum. I say think, as it doesn't seem to be centred around a single frequency (60Hz), instead it's spread across the spectrum (at least, according to the analyser I'm using in Live 7) and so it sounds more like a type of noise to me.

If I plug headphones directly into a module's output then I don't hear it. When I plug the module's output into my audio interface, then I get the noise/hum. This is what leads me to believe it's a ground loop. Am I correct? If so, how do I remove it safely? A DI box with a ground lift feature?

Many thanks in advance for any help,
Pete

p.s. to complicate matters, I'm using a G6 rack I bought 2nd hand from the US and am using it in the UK (with a step-down transformer). I don't think this is the problem but thought I should mention it in case I'm wrong.

Hi Peter

> If I plug headphones directly into a module's output then I don't hear it. When I plug the module's output into my audio interface, then I get the noise/hum. This is what leads me to believe it's a ground loop. Am I correct? If so, how do I remove it safely? A DI box with a ground lift feature?
I assume it is an interface, which is powered via the datacable from the 
computer. If i am right, then the solution will be either powering the 
interface via an separate powersupply, or connect the Doepfer to the 
computers interface via an passive DI split box (means ot 
electronically, but true split with a transformer).

This problem happens very often with computers with separated LCD 
monitors (e.g. at our sessions it happes to two persons with Apple 
MacMini plus monitor), but also sometimes with laptops.

Florian