Re: [AH] grrrround loop

From Mike SynMike
Sent Mon, Jun 11th 2018, 13:38

A ground loop buzz is most often this is solved by plugging all devices =
(including the computer) into one power source. If that doesn't work, a =
Direct Box can often fix it.

But given that your buzz stays on a specific input channel even when you =
swap the instruments around, I=E2=80=99m guessing it is a cable problem. =
Try a different audio cable on input 3. Are you sure you are using the =
same power cables as before the move? I once found that I had a power =
cable that was wired wrong from the factory.

Mike.


> On Jun 11, 2018, at 6:13 AM, Sxnths <xxxxxx@xxxxx.xxx> wrote:
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> Hello,
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> I moved temporarily my studio to my gf apartment and I can't tell if =
she worked some black magic or I am being stupid.. I am faced with a =
rather simple ground loop issue that I can't solve. It seems to be =
between a Macbeth M5 and an Andromeda A6. They both go into a RME =
Babyface. I see the hum showing up on the input(s) mixer (even when the =
speakers are off or unplugged).
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> One configuration causing the buzz is having the macbeth on input 3 =
(simple 1/4") and the Andromeda on inputs 1/2 in stereo (those are =
balanced XLR inputs but I believe the Andromeda main outputs are =
unbalanced ... not sure if I do something wrong here already). The buzz =
occurs as soon as the andromeda is plugged in and the power cable =
connected (it doesn't have to be on). The buzz is coming on the input 3 =
(the macbeth).=20
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> I tried to switched and have the macbeth on the balanced inputs and =
sure enough ... buzz occurring on input 3 again (the andromeda's input =
this time).=20
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> I tried moving plugs around, connecting to other outlets, close by, =
far, etc etc. With no luck.
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> I guess I have multiple questions at this point:=20
> - am I doing something wrong with the balanced cable? Does it needs to =
have a special wiring to go from balanced to unbalanced?=20
> - can there be some missing isolation or connection inside the =
synthesizers causing the buzz? Any way to test for that?=20
> - is there any device that can help with this? Can the power strips be =
a culprit?=20
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> Thank you in advance for the help
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