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View Full Version : Help! Hifi Electrical Noise/buzz



Vicioussid
05-10-2009, 03:48
Hi there,

I'm having some issues with my over all Hifi setup.

My Turntable going through the CA 540P Phono into the NAD 326 Int Amp and produces an electrical buzz/noise. I can hear this on the speakers and on the headphones, in particular on the Dr Dre active headies. when I first got the Phono amp I thought it was to blame so I got it replaced but same problem. I also notice when I touch the back of the phono amp the noise changes slightly.

I haven't put the record on yet, meaning the power to start the motor.

Here's the weird stuff:
1.When I disconnect the RCA connectors leading from the TT to the Phono amp the noise disappears.

So I think it must be the TT?

2. RCA are connected from the TT to Phono amp and I disconnect the power supply from the TT, the noise is still there.

Conclusion??: It is like the electrical interference is switching between paths, so when the TT is off the electrical noise goes through the RCA connectors and than through the Phono amp. What I don't get is if the TT's power supply is disconnected where is it picking up the noise from because when I take point 1. into cosideration? Yes the TT is grounded using the Phono Amp's grounding connector.


Ok to put the spanner in the works: I just got my Caiman dac and it also has this noise/buzz. When I touch the back of the Dac in particular the RCA plugs the noise disappears. I use my Dr Dre headies (it picks noise a lot more) and the noise is in stereo, now, when a track starts playing the noise shifts to the left can, dims slightly and is still audible at low volume.

I took the Dac to another room with a Mac, plugged it in and the same issue.

We've only moved into this house in March, It's a federation style Semi, however the Electrical box at the front of the house looks fairly new.

So do I have some weird electrical grounding issues or what?

Please anyone?

alb
05-10-2009, 06:59
Hi Vicious or Sid whatever.

Only twice have i had earthing problems, and both times it involved NAD gear.
I had to use a length of wire connected between the NAD casework and another component. That was the only way i could find to stop the hum.
Try poking around with some wire, but not near the mains. Have you tried disconnecting the TT earth from the phono amp, or connecting it elsewhere.
Of course it may be an interconnect issue. Maybe someone with more experience of commercial stuff will recognise the problem.

Vicioussid
05-10-2009, 07:34
Hi Alb,

The NAD, could be?

It still doesn't explain the DAC having issues as it was not connected to the NAD Amp upon first listening, just connected to the Mac via optical cable and to the headies and of course the power main.

If I disconnect the earth from the Phono amp the sound/Noise/buzz is amplified.

Stratmangler
05-10-2009, 08:24
The NAD stuff has floating earth - I have a C320BEE amplifier. I don't get earth buzz problems when using line level gear, but when I connected up my phono stage the whole lot buzzed like a bag of angry wasps. A separate earth link to the amp sorted that out.

It sounds like you have earthing issues.

Chris:)

Peter Galbavy
05-10-2009, 15:53
I had this problem.

Stan suggest that my amp, Audiolab, had similar known issues to NAD (I think, or did he say NAIM ?) grounding. I made up an crimped earthing cable and connected the case of the Caiman (via inserting a flat crimped loop thing) into the case between the lid and base and securing it with one of the four bottom screws. Then connected to the phono earth on the pre-amp and all sorted.

Themis
05-10-2009, 17:43
I once had this, it was because one channel of the TT output cable was damaged and the earth (negative? how the heck is it called?) was not soldered anymore.
Check both TT outputs, as well.