2. analog
  3. 165361-151430

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
chakster's avatar
chakster
6,144 posts
 
In external phono cable, especially  used one, the problem can occur in the soldering joints, it can be inside RCA or DIN, each connector can be inspected and re-soldered. 
Post removed 
starwarrior
52 posts
 
Check the continuity of the turntable ground wire. Secondly make sure that the ground termination makes it to the tonearm. An SME 3009 tonearm as an example is mounted on rubber grommets. If the cable ground is terminated at the chassis it may never make a physical connection with the tonearm. Another interesting issue is if the tonearm wires employ the use of Litz wire where the strands are individually insulated. If so the insulation has to be scraped off before soldering.

Just sayin,
Starwarrior
Thorens Td124/Mac Ma275/Mac C2700/Manley Massive Passive/Brennan B2
esputnix OP
19 posts
 
Thank you for your considerations! Exposing the ground cable wire and connecting it to the phono stage grounding pole fixed the hum issue. It now performs as expected. 
More to discover