Ground loop noise problem

[rubis]

Hi

      can anyone offer any advice on how to eliminate ground loop noise from my recording efforts

The set up I am using at the moment is an Asus laptop, Audient ID14 interface and Reaper 

The drum tracks with BFD3 are, as you would expect, hiss/hum free, but when I add bass and guitar parts there is unacceptable background hum. This is still noticeable when I use my P bass (I thought the pickups were humbucking?) and it is very noticeable when I use my Gretsch 6 string which has dreaded single coils! 

I have tried using a Behringer HD400 hum eliminator, but this has marginal effect

I should add that the laptop, interface and a mains powered USB hub are all plugged into a six socket extension lead 

 

Anyone had similar problems they were able to overcome?

 

thanks in advance 

Harry 

 

[Skol303]

Yep! I'm very familiar with being plagued by ground loops

And they can be difficult to pinpoint... you basically have to work through your signal chain, methodically unplugging/plugging stuff in until you find what's causing the hum... or not. With just a bass and amp (possibly also a mic?) it should be relatively easy, and from what you describe the culprit is almost certainly going to be at the guitar/amp end of things, caused by interference with any nearby home electrics.

In the end I bought one of these and it solved the problem completely; literally no hum at all. They're quite expensive brand new, but if you're patient they do occasionally crop up quite cheap second-hand on eBay, which is where I bought mine:

Ebtech Hum Eliminator HE-2-XLR

Edited March 9, 2018 by Skol303

[DaveFry]

Test to see if the noise persists if you try running the laptop on it's own battery .          

[SH73]

I have the same issue and the behringer box want back to Amazon promptly.

The way I tackle ground loop is this. When I record , I pull out the jack end of the power source for the laptop. This instantly kills the ground loop. 

I plug it back in when I listen to track or mix/master/edit.

Someone recommended this. I have not tried it.

[rubis]

Thanks for the replies, this is something to be getting on with 

I think the main culprit may be the guitar, a Gretsch 5420t, the pickups are not humbuckers and being hollow body it would not be possible to shield it

I was thinking of trying some better leads, (I use Whirlwind at the moment) can anyone recommend anything optimised for recording (I don't gig anymore)?

 

[DB5]

I get shielding type noise at home and I solved it by accident when I connected a mic cable to ground via the interface - i.e. the bass was connected to the 1/4 inch direct in and I also had a mic cable running from my amp DI output into the interface mic input. Amp doesn't need to be on but connected to the mains. I'm using an Audient ID4 and I was using Motu before. Give it a go!

Edited March 16, 2018 by DB5
correctness

[rubis]

cheers, I will

[bazzbass]

firstly, plug the laptop into a different power outlet to the rest.

Second, buy a cheap passive DI with a ground lift switch.

Use it.

[rubis]

Nice one bazzbass

[bazzbass]

It might not work, but it is the cheapest option to try and the DI should be in your arsenal anyway