I heard today at a Tech Summit that sometimes I come down hard on people, but jeez -- what the hell brand and model of turntable is this? Can we PUHLEEEZE HELP by knowing what the product is?
Here's what I'd do. Put the two turntables next to each other on a table, with an AVR or integrated amp and a pair of speakers on the table. Hook each one up in turn. See what happens. I mean, you say it's a 70 foot run but you don't say you've tried the turntable without the 70 foot run.
If you did this, then forgive me -- it wasn't clear to me that you had.
As for where to connect the ground, it should go to the chassis, the metal parts, that the motor is connected to. With more modern motors it might be necessary to play with several ground locations to find the best one. And find out with an ohmmeter if either of the cartridge output grounds is connected to the chassis; in the past, neither cartridge ground should be connected to anything except the RCA cables connected to the outputs of the cartridge.
By the way, what's in between the cartridge and the seventy foot cable?
A good answer is easier with a clear question giving the make and model of everything. "The biggest problem in communication is the illusion that it has taken place." -- G. “Bernie” Shaw
