Ground loop or some other line noise with an IR loader between amp and PA system input

[pipelineaudio]

I'm using IR pedals from the line output of popular vintage Fender dinosaur amps into the PA system, and getting what sounds like a ground loop.

These particular amps don't have ground lift switches or polarity switches. The pedal doesn't have a ground lift.

I tried using a DI in between which did help a lot, but not perfect. I tried using a ground lifting power adapter on the amp (the same three to two prong things you probably have a hundred of) and it helped a lot but still had a buzz.

I was looking at the Morley (formerly Ebtech) Hum Eliminator, but it says "Note: The Morley Hum Eliminator isn’t intended for use with mic- and instrument-level signals or powered speaker lines."

I guess I could put this before the IR loader as that should be a line level signal, but is there something better for this?

https://www.sweetwater.com/store/detail/HumElim--morley-mhe-2-channel-stereo-hum-eliminator

 

[bikescene]

Line level is the intended level for those isolation devices. Though you might have to watch the level going into the cheaper IR pedals. I've read that some of those don't sound so good with hot levels.

I used to have a Hotone Binary IR pedal that I ran my loaded down amps into. I ran into ground loop hum, despite the line out of my Suhr Reactive Load being tapped off a transformer. I found devices like the Ebtech Hum Eliminator and the ART DTI to be useful in getting rid of the noise.

The Lehle P-Iso probably would be a higher end version of a line isolator, but I've been satisfied with my Ebtech and ART devices.

 

[pipelineaudio]

I need to try these. The lack of ground lift on the sonicake ir loader is giving me some grief. I tried putting a DI in the way to isolate but no luck.

 

[pipelineaudio]

Epic fail on me. I totally forgot again that the sonicake IR loader has a 1/4” out in addition to the xlr. If the band on stage takes a break I’ll try and swap it in. 1/4” out to the direct box

 

[EOengineer]

Have you run the same chain into your interface to confirm it’s not something being generated in your rig?

 

[pipelineaudio]

Alright, that worked perfectly! Ir pedal 1/4” out to DI. Epic win.