for anyone getting noisy output (ground loop noise) when plugging OP1 via USB + Audio In/Out

i just scooped one of these ground loop isolators off ebay. its about the size of a AA battery.

my op1 (as well as other usb-midi gear that i've tried) is silent now when using the USB cable & audio cable!
no more added ground loop noise!

i've seen some threads in the past w/ other operators experiencing this type of noise so i thought i'd share.

theres a lot of options out there for this type of thing, but this one was the cheapest & smallest that i could find ~$10.

Thanks Doc!


for European people, I bought this one from Juno records... the heaven reached with 4.65euro :)

Hello, I have the same issue even if my OP-1 doesn’t charge via USB. Would a stereo DI box help? Something like this?

if i remember correctly when i researched this
the ground loop noise doesn’t have anything to do w/ charging
(which is why the turning off charging option doesn’t help either)

it has to do w/ the usb midi and audio sharing grounds and the way USB is designed

personally, a DI box didn’t help me in my situation, the lil ground loop isolator totally did.
but maybe yours is different. only one way to find out

in theory that is correct. in practice there seems to be a difference in noise when the OP1 is charging from the USB bus and when it’s not. my setup here is fairly sensitive to ground loops but of the whining bus noise type - and turning off charging removes the noise I otherwise experience. an ymmv thing…

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