Matriarch OSC bleed, Clock Ticking, Speaker Popping on Power = Bad PSU

[jonmanness]

I've seen a few random posts on the web about this, but I thought I'd share here in case people are frustrated with noise bleeding from the Matriarch (and also Grandmother I believe but I don't own a grandma).

I recently added a Roland SP-404MkII to my rig for live shows, and noticed OSC bleed and clock clicking from the Matriarch, even when the channel was muted in the mixer. The unbalanced design of SP404 revealed some grounding issues from the Matriarch that I had not noticed through the balanced connections of my UA Apollo. Powering on and off the synth also made my monitors pop, even though the I had the synth muted in the mixer.

The Fix? Lifting the ground on the Matriarch power supply by adding a three-prong to two-prong adapter fixed everything above. I'll probably reach out to Moog about a replacement power supply for a grounded connection, but I'm happier that the synth isn't humming or clicking anymore!

-Jon

[Aszazin]

Yes, I have a Grandma, and the supplied PSU is a bit crappy.
It's indeed through the earth things are picked up. It even bleeds the earth when the synth is turned off.

The PSU is bad by design, best is to change to a PSU which isn't plugged into an earth, or a dedicated PSU for audio purposes, such as the iFi iPowerX. You need 12V 2.0A DC output.

I'm not sure not connecting the earth to a PSU which is designed to be connected to the earth is a good idea. Probably there is a reason it is earthed...

[pmumble]

The Grandmother has the most noise of any synth in my studio, except maybe the Matriarch when it is powered down. I get around it by running it eurorack out and then from my modular through a balanced output.