one channel hum Help

[madscientist]

Hi Guys

My system seems to have developed a one channel hum through the right channel that increases with volume. It is only noticable when i am using the phono setting on my pre-amp, the cd and aux settings are silent. I have checked the polarity of the cartridge tags on the tonearm and they are correct, i have also checked that none of the tonearm wires are touching. I have also tried the earth wire from the tonearm attached and un-attached to my pre-amp. Also turning off the power to the turntable made no difference.Any suggestions for a probable cause or cure?
Cheers
paul

[Ali Tait]

Do you have a separate phono stage?

If so, try earth wires between the phono stage, pre and power amp, and combinations of this to see if it resolves the matter.

Also, try moving your components around, that may help.

[struth]

as above. also try keeping the phono stage as far away from the amp as possible and far as poss away from mains cables ...ditto with signal cables and mains cables...also wireless devices etc.

[madscientist]

The TT is linked to a Rothwell SUT then fed into an Exposure XIV pre-amp with its own phonostage.

[Ali Tait]

Try linking the SUT chassis to pre chassis. Also try an earth from the pre chassis to the negs of the phono sockets.

[walpurgis]

Is the metalwork of the arm earthed to the turntable motor assembly?

[madscientist]

Interesting any idea of how to do that with a Notts Analogue TT?

[hifi_dave]

That won't make any difference to a right channel 'hum'.

You need to swop left and right cables one at a time to localise the hum to determine if it's the cartridge, arm/lead, Rothwell, Exposure or incons.

Which arm is it ?

[madscientist]

It is the Ace Spacearm

[hifi_dave]

On another forum, you state that the SUT is next to the power-amp. That is the worst possible place it could be. Before doing anything else, you should move it as far away as possible.

[walpurgis]

On another forum, you state that the SUT is next to the power-amp. That is the worst possible place it could be. Before doing anything else, you should move it as far away as possible.

Very good point!

[madscientist]

thanks dave

[hifi_dave]

If that doesn't cure it, I will be surprised but if it doesn't, then start to swop left and right cables, starting with the arm leads.

[madscientist]

Thanks to all problem now sorted..the SUT position was the culprit

[Ali Tait]

Good when it's an easy fix.