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Scarlet 2i2 Interface-Ground Loop Noise

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Scarlet 2i2 Interface-Ground Loop Noise

Postby chichi » Fri Jun 26, 2020 11:25 am

Hello Guys,

I have been using Scarlett 2i2 Audio Interface, and when I turn of 48V there is this annoying noise which I believe is a Ground Loop. When I unplug the power cable from the laptop the noise goes away. And when I connect it to an iMac also the problem is there.

I have contacted Focusrite about this issue and they suggested various remedies which haven't worked and all my friends who have been using this Audio Interface have had the same issue.

Any of you guys had the same issue?

Any suggestions?

Thanks
Chi
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Re: Scarlet 2i2 Interface-Ground Loop Noise

Postby Hugh Robjohns » Fri Jun 26, 2020 12:41 pm

I've no idea why turning off 48V phantom produces this problem. A ground loop is present the whole time. And usually the loop exists between the computer and mains-powered monitor speakers, so the typical solution is to disconnect the ground connection that runs from the interface to each speaker via the screen of the balanced audio cables.

You can do that either by physically cutting and isolating the screen connection inside the plugs at the speaker ends -- being a balanced connection, the signal transfer does not require the ground connection, or by using an isolation transformer box like the ART DTI (others are available).

If the noise is related directly to the use of phantom power, then something else more insidious is going on...
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Re: Scarlet 2i2 Interface-Ground Loop Noise

Postby chichi » Fri Jun 26, 2020 12:56 pm

My bad-That's a typo Im sorry-It should be when I turn ON 48V.

Thanks Hugh for the reply.

In this case I have not been using any speaker-I use Only headphones.

And I can see the noise being recorded in the project file which is really annoying.
chichi
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Re: Scarlet 2i2 Interface-Ground Loop Noise

Postby chichi » Fri Jun 26, 2020 12:57 pm

chichi wrote:Hello Guys,

I have been using Scarlett 2i2 Audio Interface, and when I turn ON 48V there is this annoying noise which I believe is a Ground Loop. When I unplug the power cable from the laptop the noise goes away. And when I connect it to an iMac also the problem is there.

I have contacted Focusrite about this issue and they suggested various remedies which haven't worked and all my friends who have been using this Audio Interface have had the same issue.

Any of you guys had the same issue?

Any suggestions?

Thanks
Chi
chichi
New here
Posts: 5
Joined: Mon Jun 22, 2020 10:45 am

Re: Scarlet 2i2 Interface-Ground Loop Noise

Postby Hugh Robjohns » Fri Jun 26, 2020 1:28 pm

chichi wrote:It should be when I turn ON 48V. In this case I have not been using any speaker-I use Only headphones. And I can see the noise being recorded in the project file which is really annoying.

In that case I'd say its unlikely to be a conventional ground-loop, and is more likely to be an issue with the power supply that generates the 48V.

What else is connected to the Scarlett?

What are you powering with the phantom power?

And assuming it's a mic, how is that mic physically mounted? (Just in case there's a ground path via the mounting arrangements).
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Hugh Robjohns
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