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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

Showing 3 responses by esputnix

esputnix OP
19 posts
 
1. Disconnecting tonearm ground wire from the phono stage did not make even a bit of the difference. With or without the tonearm ground wire bolted to the Ground Post of the phono stage makes no perceivalbe difference in anything. I wonder if this a Ground post or a tonearm ground wire that doesn't ground at all. Should be any hearable difference in hum when we connect/disconnect the tonearm ground wire?

2. The tonearm is SME 4. It looks silverfish plastic (I think it is painted magnesium). I guess I should be able to connect a ground to it safely... Thank you for your suggestions!  
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. 
esputnix OP
19 posts
 
The cable that hums is used. It was purchased on Ebay. The issue turns to be behind the broken ground wire. There is a crack right where it meets the spate connector. I wonder if it would be OK to just detach the spade connector from the ground wire, open the wire insulation at the end and wrap the exposed ground wire around the Ground Post of the phono stage? Would it be any side effects in exposing the ground wire or it has to be terminated by spade connector?
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