[boatman7]

Hello All -

My Dual 606 has a minor amount of hum in the left channel only. Generally speaking . . . where does hum come from?

Thanks / JB

 

[Sarchi]

Well it's usually related to electrical grounding....but in an old turntable there are many places you may have to look.

I would try the following, in order:

Swap the L-R phono plugs going to your preamp. If the problem switches to the other channel, try plugging another source in and see if you still have the hum. If you do, it's the preamp. If not, it's the turntable.

Assuming it's the turntable...it might be easiest to swap the cartridge out and see if that's the cause. Other causes may be the cartridge leads, or tonearm cable.