Ground loop, solved before posting, but why?

tekbow

This one is a conundrum.

Long story short, there was ground hum coming from the below board, tracked it to the Mimiq at the end.

Stuck an isolation transformer (great things) on the secondary lower output, problem solved. The Mimiq Has it's own dedicated outlet on the PSU.

Now I initially missed it because there's 2 keyed gates in my amps FX loops which are very effective.

However this only seems to have appeared since setting up in my new house as this wasn't an issue without the gates in my old house.

Why might this have materialised now? Fault in the pedal? Something else?

Considering my recent thread on anal cable management for my new gear room, some may suggest that as a cause. It's worth pointing out that if I drop the mimiq out and come straight of the bright onion AB/Y, there's no hum.

WiresDreamDisasters

Probably something to do with the house wiring, the rings, or ghosts.

Always good practice to have some sort of lift or isolator if you're doing fx-loopy stuff anyway, IMO.

ICBM

Two amps with both inputs (or FX loops, it makes no difference) fed from a common ground will cause a ground loop. Whether it actually generates hum or not depends on various factors, so it may well do it in one location but not another.

The Bright Onion has the second output ground-isolated, I'm fairly sure.

tekbow

ICBM said:

The Bright Onion has the second output ground-isolated, I'm fairly sure.

It does, which is why there's no issue going out of it I suspect.

Soon as the mimiq Goes after it, that's where the issue is.

But, like I said, solved with the orchid transformer on the second output of the Mimiq.

Guess it's going to be a permanent fixture now though. Better order another.