Live with A Hum vs. Buy An Outboard Phono Stage

It can be, but often a hum can be caused by a phono stage, one that is in the pre-amp, or an outboard one, that is too close to transformers, especially in amps, and the cables from the TT to the phono stage must also be placed carefully so they do not come close to a transformer or PC. If you haven't already tried that, be sure to do so before you buy an outboard unit. Often just getting space (as much as possible) between the phono pre and or cables from other electronics will do the job. You probably already knew that and eliminated these possibilities. So....

If you can get one that will match your cartridge and have a return privilege, why not - the ones you mention are inexpensive enuf.

Newbee,

The phono input even hums when no phono is even there. After seeing that, I tried the shorted interconnects. When I got no hum then, I proved that the preamp wasn't at fault. I haven't been able to identify an extraneous source, so I wrestling with the question of buying an outboard unit. I may just have the same problem with that, however.

Lee

You should be able to determine what is causing the hum through an organized trial and error. Don't live with it. Isolate it and fix it.

Lee -- Towards the end of your original thread about this problem the hum disappeared, returned, and disappeared again as you did various things (reversing plug polarities, separating and shielding components, etc). Obviously it has now returned once more.

Therefore, what I'm thinking is that it may be an intermittency in the phono stage of the preamp, which happened to not be occurring when you shorted the inputs. So ruling out the preamp on the basis of that experiment may not have really been conclusive.

If it is an intermittency in the preamp, my suspicion would be that a capacitor may be on the edge of failure, as you were led to believe way back at the beginning of that other thread.

Does the problem seem to be temperature or warmup sensitive? If you are not sure, try putting the preamp in either a cold basement or a warm attic for a while, and see what happens.

Beyond that, I agree with Newbee's suggestion to try to get a separate phono stage with return privileges.

Regards,
-- Al