phono hum problem

Hi, I have a receiver (Pioneer Elite, a few years old) and just bought a turntable setup. The turntable (Pro-Ject Debut Carbon EVO) comes with a 6' cable with built-in ground wire, but the cable isn't long enough to reach the receiver. So I got F2F adapters, plugged in another 6' phono cable, and connected that to the receiver's phono input. I got significant high-frequency hum. Then I extended the ground wire with some lamp cord so that I could connect it to the ground terminal on the receiver. Now there's a lot less hum but it's still there. The hum gets louder as I turn the receiver volume up, and it's only on the phono input. Any suggestions on getting rid of the hum entirely? E.g., should I replace this spliced-together cable with a single longer cable? Or is it more likely that the phono preamp stage is producing the residual hum?

September 6, 2023 - 11:36am

hoytis

Offline

Last seen: 1 week 4 days ago

Joined: May 19 2021 - 10:37am

First thing I would do is

First thing I would do is disregard all the extensions you bought, place the turntable close to the receiver and use the stock cable/ground alone. Obviously, this isn't the place where the TT will reside permanently, but just for test purposes. Any hum?

I'm not sure what kind of extension cable you bought but if it's not designed for low capacitance it might not be shielded appropriately. Phono signals are very delicate and easily subject to interference. When you try to send that signal over extended lines it can deteriorate. If you were doing all this with a CD player, no problem. It's already line level. But you're trying to send a very weak signal before it gets turned into a line level.

Search form

You are here