Dreaded Ground Loops

I’m having problems with ground loops between Herbert and all other amps.
Everything else seems to play well together.
I was splitting passively at first but now have a Radial JD7 and it has reduced it, but the noise is still too much for recording Herbert together with another amp.

Anyone had similar problems and come up with a solution?
Any ideas what to try next?

Thanks

rickenbacker198":1y5ykax7 said:

I’m having problems with ground loops between Herbert and all other amps.
Everything else seems to play well together.
I was splitting passively at first but now have a Radial JD7 and it has reduced it, but the noise is still too much for recording Herbert together with another amp.

Anyone had similar problems and come up with a solution?
Any ideas what to try next?

Thanks

Click to expand...

My weapon for ground loops is an EB Tech HE-2.

https://bit.ly/2I2J1Lb

Are you plugged into the same outlet? Does it do this with other amps paired with one or the other? Also I swear by power conditioners. Are the pedals on an iso supply? Etc. The more info the better I can help.

swamptrashstompboxes":3m04qhl3 said:

Are you plugged into the same outlet? Does it do this with other amps paired with one or the other? Also I swear by power conditioners. Are the pedals on an iso supply? Etc. The more info the better I can help.

Click to expand...

I’m plugged into the same outlet.
No pedals.
It’s Herbert combined with any other amp that's the problem.
All the other amps seem to work well together.

If I have Herbert plugged into the JD7 but not even engaged.
It adds noise to the other amps.

The JD7 was just at Radial to be checked over because I figured it was faulty.

Ok so finally I found the problem.

I just had solved another ground loop problem with a mic preamp and was feeling the strength to take on this one again.

So I hooked up the VH4 and Herbert with the JD7.
I have tried absolutely everything I can think of.

I just happened to wiggle the power chord on the back of Herbert and there was a lot of crackling.
Thinking bad power chord , I swapped it. No difference.
Tried deoxit , no change.
Kept fooling with it , If I could wiggle and hold it just so, the noise would cut out completely but the amp sounded fine.

So I was thinking the power socket on the amp is bad.
I opened the amp and noticed the chassis ground is connected to the power socket by a short lead.
Then I wiggled the chassis ground connection and it and it rotated freely.
The ground was on the screw connecting it to the chassis but not tightened down!!
By wiggling the socket I was pulling ever so slightly on the chassis ground, helping it connect.
The chassis ground screw seemed tight because there’s a lock nut holding it on the top side of the chassis.
I’m sure this was the case from new.

I loosened the lock nut and tightened up the chassis ground.
Dead silence.
Thank God!!
I was losing my hair on this one..

Such a wired issue because whenever Herbert was plugged in alone never a bit of noise.

Thanks for the input guys.

Glad You figured it out. Quite the goose chase.