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Hum after replacing tonearm cable

After replacing my entry-level tonearm cable with the high-end one there is now a very audible hum once the turntable is on and its motor is spinning. Moving the turntable around, away or closer to the phono stage or rotating it 180 degrees or upside down did not make any difference on hum. It is consistant regardless where the turntable is or how far or close it is to preamp or amp. The hum is equally loud in both left and right channels. Is there anything that could be checked or done to fight the hum other than switching back to my entry level tonearm cable?
esputnix
petg60
1,486 posts
 
What happens if you swap back the old cable?

G
mastering92
870 posts
 
what do you mean by high-end cable?

I suspect it is not 100% compatible or the new cable you bought has a design defect. If possible, switch back to the original cable and test it. Then power down (for about 5 minutes) and test the new cable. This is so you can figure out if there is intermittent failure or consistent failure in the new cable.

At any rate, you could always flag to the manufacturer and get your money back.
elliottbnewcombjr
5,111 posts
 
put the old cable back on. problem gone? then it's the new cable.

if hum with old cable, then it's not the new cable, something got disturbed, 

Din connector? RCA termination block? Tonearm wiring? 

hum in both channels is a hint.
mijostyn's avatar
mijostyn
8,175 posts
 
You need a meter to figure this out. I suspect signal negatives are being shorted to tonearm ground. Some tonearms do this. Check ground continuity of the cable. It should be isolated from the signal negatives. Do the same at the tonearm. If the tonearm is in reality a 3 wire arm then you will have to use the old cable or do significant surgery to the new one. 
chakster's avatar
chakster
6,144 posts
 
I thought you arm was rewired internally too. 
Or you are talking about external cable only? 

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