Turntable/cartridge weirdness

I have a Rega P6 w/ Exact cartridge. Recently, the left channel went out, so I started my diagnosis. Here's where it gets weird. When I use my outboard phono pre (Pro-Ject phono box 2), there is crystal clear audio coming out of the left channel. Nothing out of the right channel. So I swap cables and use the built in phono pre in my Mac C37 system controller, the audio now comes out of the right channel and sounds not as good as w/ the outboard pre. The balance knob is @ 12 oclock, out of influence. So I pushed gently on the cart wires, repeted the test, same thing. Anyone want to take a stab at this? Thanks! David

 

If your getting only one channel from both the internal and external phono, I’d check the leads coming from the cart.

 

I disconnected all leads and reconnected them, same thing. Time fir the shop, I guess.

 

Which leads did you disconnect/reconnect, and why did the problem move from left channel to right channel when you changed phono preamp?

Normal troubleshooting would have you (carefully) swapping the left/right wires going to the cartridge pins to determine if the problem is in cartridge or in the tonearm cabling, but I think now you need to get back to the baseline configuration and figure out why the channels swapped when you connected to a different phono preamp, unless you intentionally did that. If it's going to the shop, you should give them a clear explanation of the problem.

 

That only means that the issue became further confused because you did too many things at once. Always change only one thing at a time when troubleshooting.

Using the Pro-ject Phono Box, connect the turntable normally. If the left channel is still out, switch the left and right turntable output cables at the Phono Box input. If the problem moves to the right channel, it's a cartridge or turntable cable issue or tonearm wiring issue. If the problem stays in the left channel, it's a Phono Box issue.[/QUOTE]