• Registered: 2009-12-27
  • Posts: 15

Topic: Babyface - noise from instrument and mic inputs.

Hi,

Two questions:

1) I connect my electric guitar to the right side of my Babyface (high-z input) and I hear a high frequency noise like "zzz" sound from my headphones. The closer I physically get the electro-guitar to my Macbook Pro computer and Babyface near it, the more noise I hear. Now I've heard there maybe a ground loop problems with Macbook Pro and USB hubs? I disconnected all AC cables from the outlet and ran my Macbook on battery - the same noise exists. Guys from Sweetwater advise me to buy an external DI unit with XLR adapter in it so it could cancel the ground noise. Will it really help in this situation?

2) Also, when I connect my SM57 mic to the Babyface directly to the XLR input without any external preamps I also hear a noise but a different one, like a room noise.. My Gain is set to about 42DB and my room isn't noisy at all. Is there a way to get rid of this noise or weaken it as much as I can?

Thanks!

2 Reply by MC

  • MC
  • MC
  • Administrator
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  • From: Germany/Thailand
  • Registered: 2007-04-06
  • Posts: 25,599

Re: Babyface - noise from instrument and mic inputs.

1) With both Macbook and BF on battery the noise is the normal radiation from the computer into your pickups. Or the guitar cable is not good enough.

2) Try the other input to compare, and also don't use the extension cable when testing this.

Regards
Matthias Carstens
RME

MC's Website

  • Registered: 2008-11-07
  • Posts: 34

Re: Babyface - noise from instrument and mic inputs.

Hmmh. You got me thinking.

"normal computer radiation into the pickups" ... ...whatever that means.

1. Isn't there any reasonable common-mode noise isolation in place?
    We all know that USB is an awful noisy interface.
    If not isolated properly it usually generates nasty polluted groundloops.
    Hasn't  RME applied any serious measures to get the noise/groundloops under control?


2. Do I need to run on batteries - the computer and the BF - to get the noise floor down?
    It that what your answer implies?

3. Are you implying that the extension cable is causing extra noise ?


Looking forward to your answer.

Cheers