Ground loop or buzzing Hermod at high gain


Was wondering if anyone could test this for me.

  1. Hermod powered in a case, nothing plugged into Hermod.
  2. Line out of any VCA or Mixer within the same case into an audio interface. (no audio plugged into VCA or Mixer)
  3. Audio interface gain turned way up.
  4. Digital buzz and humming from the Hermod that changes character depending what mode you are in.

Just wanted to see if anyone else gets any noise, typical recording levels of a source mask this noise because the audio interface gain is never turned up high enough to pick it up, but it’s still there.

I’ve tried multiple cases and power supplies, I have surge protected power bars and have put all interfaces on the same power brick.



I wonder why squarp ignoring so much issues with ground bleed?!

I don’t think they are ignoring, if you contact them directly they will be happy to try to help you out.
But I’d assume it’ll be a hardware issue so I doubt they can fix it ( except with hardware revision)

Digital noise is not uncommon in racks with more complex digital modules , partly because eurorack is a simple ‘standard’ that does not try to avoid noise.
it’s also highly dependent on your setup,
so its much worst for some than others (hence why not everyone is complaining about it).

Personally I’ve not had many issues with it,
except some ground loop noise occasionally when connecting the pyramid via cv - usually with a bit of messing about I can then get rid of that.

I have contacted Squarp and they said they could take a look at my unit, I haven’t sent it in yet because from what I’ve read this may be likely the units interaction with switching power supplies and the module being digital.

From my research online, it would appear if I had a linear power supply this issue may be remedied. It is quite annoying however on both the MakeNoise and Doepfer PSU3 there is a quiet ground loop being created and changes frequency depending on how many LEDs are lit on Hermod. When the modular is emitting sound this is masked to some degree. But when I have no sound playing on a patch and I bump up the gain quite high on my audio interface or mixer there is a high frequency ground loop type noise sitting in the background Removing the unit from my case and the noise disappears.

I would be curious if other people with switching supplies could test this with a patch connected but no sound playing with their interface gain increased to see if they experience the same issue. This would help me determine if I should send my unit off.

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I have the same issue. It’s most noticeable when patching between my IJ Palette and 7U (both switching PSUs).