Two Turntables and Hum Problems - Help Please

In addition to the good comments above, another reason that a 30 foot run from turntable to phono stage is unreasonable is cable capacitance. With a moving magnet or other high output cartridge, sonics will be significantly degraded unless you use a cable having extremely low capacitance per unit length AND the cartridge is specified to work into high load capacitances. With a low output moving coil cartridge that may or may not be an issue, but the likelihood of noise problems will increase significantly.

Get a separate phono stage, as Stan and Elizabeth suggested.

Regards,
-- Al

I've had signal degradation with 12 foot cables from the turntable. You may not realize it unless you could compare the shorter length first. Upper end treble loss, no air, and it was just plain boring sounding. If I didn't know how it sounded before the longer cables, I may have blamed a lot of other stuff first, and wasted money.

Running a 18 awg for the ground temporarily may help hum.

In the long run, move them closer, or get a phono stage as mentioned above.

Thanks, all, for your suggestions. The length is more like 18-20' not the 30' I mentioned originally. My setup and physical layout of the room and the audio rack preclude my getting the two TTs any closer than they are currently. I'm going to distill the advice you've given me and try to solve this issue. I've had a busy schedule recently but must try removing the sub woofers from the equation, temporarily to see if that helps.

Getting 20-24 gauge grounding wire might be another step but I'm still not sure what kind of wire I should use. Hmmmm.

The extension phono cables could also be an issue. Perhaps a heavier gauge of female to male RCA phono cables could help things. Thoughts?

Thanks all. I'll check back for further responses soon.

SNazz

18-20 feet is still mighty mighty long for a cable transmitting such a miniscule signal. Above all other cables I would try to keep the phono cable as short as possible (and make sure it was shielded). Without shorter phono cables (or maybe balanced cables) I would be surprised if you are able to get the hum out of the vinyl setup.

The gauge of the rca extension cables won't make any difference. What is important, in addition to shielding effectiveness (which is hard to predict) is (as I mentioned earlier) keeping cable capacitance as low as possible, particularly if you will be using moving magnet or other high output cartridges. I suggest Blue Jeans LC-1, which provides very low capacitance per unit length at a relatively low price.

For purposes of minimizing hum, the kind of grounding wire you use is not critical, as Elizabeth indicated above. I suggest initially experimenting with whatever is handy, or whatever you can get cheaply and conveniently at Home Depot, Radio Shack, etc.

If and when you eliminate the hum, however, you may then find that you are picking up radio signals or other interference. To address that kind of problem, the best type of ground wire would be a "braided ground strap." Google that term for further info, if necessary.

Regards,
-- Al