Hum in my AR2ax's

[Guest]

I recently had my Dual 1229 repaired. Connecting it last week-end resulted in a VERY loud hum. I can't remember from reading (a long time ago) in various hi-fi magazines what the cause of that is. Are the speakers too close to the turntable? Does it have something to do with the cable shielding? I tried to touch the ground wire from the turntable to the receiver but there is no noticible reduction.

Can anyone help?

Thanks in advance.

Kip

[Guest Nigel]

Kip;

Speakers too close could be the cause, but not likely.

When you say you just got it back, did the place that had it test while you were there?

The hum is usually 60Hz.

Try plugging all of your equipment into one power strip, making sure power cables do not run parallel to audio cables.

Verify that the hum is only there with the turntable operating.

I might have some more guesses if you can give us a complete system description.

Nigel

[Guest]

In addition to nigel's thoughts, are the polarity of the plugs the same? Also, try running your ground wire from your turntable to your receiver and then to the outlet cover screw.

[administrator]

Usually when I hear any humming from my speakers it ends up being a ground loop .. last time I experienced this was when I introduced a Nintendo64 into the circuit of my A/V system. The humming would only go away if the Nintendo64 was turned off.

I eventually took the three prong power from my (very) heavy duty HK Citation 19 poweramp and plugged a 2 prong adapter on it and then into the wall. Ground loop was gone along with the humming.

I'm not sure what the specific ramifications are of losing the ground plug when going from 3 prong to 2 prong via an adapter, but it works fine for me.

Mark