1 Topic by Bandido (edited by Bandido 2011-08-26 16:11:36)

  • Registered: 2011-07-20
  • Posts: 12

Topic: Ground Noise - Babyface + Laptop.

I can't belive my eyes (and ears).

I connect my new babyface to my laptop.

I work with battery (no power supply). I mean... there's NOTHING plugged to a 220 V socket

Only babyface + laptop: no preamps, no monitors, NOTHING plugged to a 220 V socket !!!

I connect different guitars to instrument jack input and phones. (No breakout cable)

I can hear a ground noise if I put gain at 24-30 dB. If I don't play... silence guitar... the meter stays at -78  or -79 db in totalmixfx. IF I PUT MY FINGER ON PHONES CONNECTION it downs to -89 dB. When I put my finger I am the ground.

What happens ???

Any idea?

I think I'm going to return my babyface to thomann...

  • Registered: 2011-07-20
  • Posts: 12

Re: Ground Noise - Babyface + Laptop.

Details of the test:

1 .- I connect the babyface to the laptop via the USB cable. To avoid electrical problems I'm working with the laptop battery, without connecting to the grid.
2 .- I install drivers and update firmwire, the latest version of the RME website.
3 .- Connect a Gibson les paul studio, newly purchased at Thomann to the instrument input, via a cable planet waves also bought in thomann a few days ago.
4 .- Connect the headphones to the phono input.
5 .- No other cables connected: the breakout cable is disconnected.
6.- There is nothing more connected. Guitar -> Babyface -> Computer. Neither mic preamps, and pedals, no effects, nothing.

With this configuration the signal recorded at different sequencers (Cubase, Ableton Live). I get a noisy signal, with ground noise. This noise disappears if I touch the connector on the headphone jack or if I make contact with the brass buttons of the babyface. It also disappears if I touch with my finger on the metal part of the pickup selector in the gibson. But not disappears when I touch the strings or the bridge of the guitar.

As if that was a problem with the guitar I've tried three different guitars and a bass

- Gibson Les Paul Studio (Thomann)
- Epiphone Les Paul Standard Plus (Thomann).
- Epiphone Les Paul Custom.
- Ibanez Bass

The problem persists with all instruments.

For if it were a computer problem I tried with two different computers:

- Packard Bell 241SP HR-TS11 (i5 2410M, Windows 7 64 bit).
- Desktop Computer Mac OS X 10.6.6 connected to the grid (220 V)

The problem happen on both computers

Other tests I have done:

- Use different cables.
- Disconnect the headphone jack. Record the signal without hearing it.
- Connect the breakout cable. The noise increases. Decreases if I touch the metal housing of any XLR.
- Connect the guitar to a preamp Universal Audio LA-610 mkII.  Guitar -> Preamp -> XLR out  (preamp) -> XLR Line In L (babyface).
- Set the power state of windows to work in high yield. Disabling the automatic shutdown of USB.

With any of these tests  I ALWAYS have the problem.

3 Reply by MC

  • MC
  • MC
  • Administrator
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  • From: Germany/Thailand
  • Registered: 2007-04-06
  • Posts: 24,877

Re: Ground Noise - Babyface + Laptop.

It seems you have no ground anywhere so this might be normal. The usual problem is that both the computer and the amp connected to the BF have ground and there should be only one.

The strange thing here is the Mac - if that one is grounded the problem should not have been there.

Still headphone ground and guitar ground are connected directly on the PCB of the BF, so this is very mysterious.

Regards
Matthias Carstens
RME

MC's Website

  • Registered: 2011-08-27
  • Posts: 1

Re: Ground Noise - Babyface + Laptop.

I have exactly the same problem with noise in my Babyface.

- Two different computers (PC / MAC PRO)
- Setup with and without ground
- Diffrent sound sorce ( guitars/microphones/keyboards )

  • Registered: 2011-07-20
  • Posts: 12

Re: Ground Noise - Babyface + Laptop.

MC please help me with one doubt.

When I use this configuration:   Laptop (working with Battery) + Babyface

I have no ground because there's nothing connected to the grid. No?.

When  I use:  Desktop computer + BAbyface

I must have ground because computer is connected to the grid.

True ???

6 Reply by MC

  • MC
  • MC
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  • From: Germany/Thailand
  • Registered: 2007-04-06
  • Posts: 24,877

Re: Ground Noise - Babyface + Laptop.

I don't know your desktop computer nor the wiring at your place. Is its ground connected to earth (german 'Schuko') - 3-prong connector?

Regards
Matthias Carstens
RME

MC's Website

  • Registered: 2011-07-20
  • Posts: 12

Re: Ground Noise - Babyface + Laptop.

I update with more tests.
I have tried in another house, with ground. Same problem.
I have bought a power strip with a LED that indicates GROUND OK, and ... same problem !.
I have tried with 2 different guitars more... single coils, humbuckers, same problem.
Seeing the forum I see too many people with the same problem.
I have the silver model.
Can it be a manufacturing problem?
I can hear little interferences when i touch touchpad (laptop).

  • From: Germany
  • Registered: 2007-04-10
  • Posts: 9,558

Re: Ground Noise - Babyface + Laptop.

Have you tested other input signals besides the guitars? Like line signals or microphones?
Your audio samples don't sound like a typical ground loop hum.

Regards
Daniel Fuchs
RME

Regards
Daniel Fuchs
RME

RME Support's Website

  • Registered: 2011-07-20
  • Posts: 12

Re: Ground Noise - Babyface + Laptop.

Hey !!!

I was waiting for your e-mal repply !!.

Have you listen the samples ? Seen the photos?

The intereference with touchpad  is obvious with both guitars. (If i try with more USB device maybe I would have similar results but i haven't tested it).

THe ground noise is more evident with Gibson Les Paul, I think, because the pickups give more gain out.  I have tried with other guitars, single coils, active bass, and It appears. You say that it doesn't sound like ground loop. Ok I said ground noise, I mean that sounds like "no earthed". The  important thing is that it decreases when I touch any metal part.

I'm going to test with microphones. I send you the wav files as soon as I made the test.

Do you have any explanation for these noises? I Note in the forum that there are multiple clients with similar problems. Of course I do not know their settings and to evaluate would be precipitated by my side.

In any case, in my particular case you have seen the pictures of the tests. The tests are fairly clean with few elements involved: Guitar + PC + Babyface + Phones + Wire. This configuration should work. One of the main advantages of the babyface should be able to record a guitar in these conditions. Or I think so.

Thanks

Ricardo

  • Registered: 2011-01-25
  • Posts: 85

Re: Ground Noise - Babyface + Laptop.

I think your guitar is the problem.

  • Registered: 2011-07-20
  • Posts: 12

Re: Ground Noise - Babyface + Laptop.

Hi.

First of all, I have done more tests.

With microphones I belive that I have a clean recording without noises of any kind. (I think, I would have to listen with monitors to be really sure).

Thus it seems that I only have problems recording guitars and basses.

I have tested with different guitars and two different cables. Specifically:

- Gibson Les Paul Studio (2011).
- Epiphone Les Paul ES (Semi-Hollow)
- Epiphone Les Paul Standard Plus.
- Custom Stratocaster with Jackson and DiMarzio pickups.
- Bass Ibanez GSR 200, active.
- Harley Benton (copy of PRS).

All my guitars have problems ??.

Can be due to some kind of problem the specific location of my house? I live in a rural area. I do not think there is any significant electromagnetic interference, but I'm going crazy not to think.

It is possible that I must buy a DI box with Jensen transformers ???

It is possible that my babyface Hi-z input is wrong ??.

Help me !