Noise/hum when connecting ReVolt Bass straight into my amp

[schultheiss]

Hi folks, just got a ReVolt bass and I can't figure out what's going on. I placed it at the start of the chain on my pedalboard which looks like this:

Revolt > MXR M87 > Ricochet > Alpha Omicron > Microtubes X > Boss GEB7 > C4 Synth > HOF Mini > Ditto

Board leads into a Mesa Boogie Basis M2000 amp.

I have an XLR hooked up on Balanced Out on ReVolt which leads into channel 1 of audio interface and I have another XLR going from amp's balanced output into channel 2 of audio interface.

My tuner is hooked up to a dedicated tuner out on Mesa Boogie.

And now, for the tricky part... It's so damn noisy. It's so noisy that tuner is unusable, it's constantly registering G note being played. When I play a note and let it ring it sounds like a helicopter/vibrato.

If I hookup entire pedalboard (including the Revolt) straight into audio interface then the noise goes away. If I hookup my pedalboard (without Revolt) into amp it also works without any noise.

This leads me to believe that there is something going on when Revolt is connected to my amp (regular Out on Revolt into standard instrument input on Mesa). What might be causing this? Noise/hum is present even if ReVolt is in bypass mode, basically it messes up the signal as soon as it gets powered up.

Thanks in advance for any help!

 

[RossJohnDavies]

Good morning @schultheiss

Thanks for getting in touch - Ross from Two notes here. This sounds like the input of the amp is being overloaded by ReVolt's output. ReVolt outputs a line level signal which is significantly hotter than the instrument level signal an amplifier is specified for at its input. This can indeed contribute to noise and a harsh tone. Instead, does youe amp feature an FX return? If so, we would suggest connecting ReVolt to that!

Let me know if this helps and I look forward to hearing from you soon.

Kind regards,

Ross

 

[schultheiss]

Good morning @RossJohnDavies, thanks for getting back to me.

Unfortunately, the same thing happens if I go out of ReVolt's send into amp's Return (without anything else connected to the amp). That humming/buzzing is present and tuner is still picking up the G frequency.. I don't think there's anything wrong with my amp, it's pretty noiseless when ReVolt is not in the equation. Is it possible that there is some ground issue with ReVolt or something like that?

I noticed just now that when I plug in revolt straight into audio interface via Balanced Out with Ground/Lift switch in Ground position (de-pressed) - I can faintly hear that same noise/hum. Pressing the switch into Lift position severely amplifies that noise into hum which is probably identical to what I hear when ReVolt is hooked up to the amp.

I tried connecting ReVolt's power supply to different outlet and different power strip but it did not help. Other equipment works fine so I guess it has nothing to do with that..

 

[RossJohnDavies]

Good morning @schultheiss
Thanks for all of this info. This indeed sounds like there is a grounding issue somewhere in the system but we would like our specialists to take a look at this. Would you mind submitting a support ticket at Support.Two-notes.com and letting us know when you have done this. We can then find this ticket and get it prioritised with the team!

Thank you and I look forward to hearing from you soon.