How are phono cables different (related to hum issue)?


Wrestling with frustrating humming for weeks on a new TT. Finally inserted the cheap stock phono cable, and the hum is nearly gone. Was using spendy phono cables bought separately prior. So what's the sitch here? Shielding? Cheaper = carrying less signal? I was using the ground wire with both (and tried without, twas worse). Glad the hum is gone, the sound is duller but removing the hum makes it almost worth it. Of course now I need the color back, but not the hum. 
128x128zufan
Hi
A phono cable shall have an additional GND wire with a spade, to connect to a screw on the Amp's side. Ordinary RCA to RCA may have the hum noise problem you say you have.
The extra GND wire is essential. 
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Actually the Blue Jeans Cable, LC-1 might not be the best choice for some phono cartridge to pre-amp input combinations. In some cases the total cable capacitance can affect the high frequency response of the combination. The LC-1 has less than 1/3 the capacitance of many common TT cables.
The Blue Jeans cables are a good value, but they can rob the music of some of its life.  They are a good option for turntable use because of their low capacitance.  Depending on the level of your turntable and system, you may find them a little "soft" and lacking some high end detail.  I've noticed that even more with their speaker cables.  For things where cables matter less, like a subwoofer, they are more than good enough.  I can't detect any noticeable difference between their digital coaxial cables and more expensive ones.  Their interconnects are OK, but you should notice better sound quality with better quality cables.

As others have mentioned, there could be an issue with the cable itself.  I had some very expensive Kimber Cables that I purchased second hand based on positive experience with some of their similar interconnects.  They were a fail with my turntable (bad hum).  I returned them and was told they were fine, other than a loose screw that held the shielding in place.  I replaced them with some Kimber Kable TAK-Cu cables (which were about 1/3 the price) and now everything sounds great with no hum.

Hi @big_greg that's interesting. I'm using their Canare (not Belden) option for both my Tannoy & Zu (speaker cables). The former bi-wired. Anyhoots so far so good. I'll try my Pangea phono cable again tmrw to do a better A/B other than just the BJs are quieter. I'm using many of their ICs now also, so many I'll be listing my others soon. 

Hi @speedskater  also interesting, I'll re-insert the Pangea and do a proper A/B.