My Presonus DP preamp has slight hum on the tube channels. No hum on the solid state preamp side. It is out of warranty. Have you experienced this problem? If so, what have you done to fix it other than spend big $ on a better tube preamp?
Hey man, I've played bass for about 5 years now....But really what it sounds like is that one of your preamp tubes is going bad
the presonus amp likey only has one tube and it is likely one of those sub-compact types that is only about 1/4 in diameter and soldered down top a circuit board.
This little presonus preamp is not like a bass amp. the presonus amp likey only has one tube and it is likely one of those sub-compact types that is only about 1/4 in diameter and soldered down top a circuit board.
I think you should put together the smallest system that demonstrates the hum you can. maybe that is just the preamp and headphones? Anyways, disconnect everything you can. Then swap mics, headphones, cables and so on. Prove to your self that the problem sticks with the preamp, no mater what else is connected. Change out wall outlets or source of power (power cube "wall worts") too. If the thing still hums then it is going to need repair. Send it in or if you have the skills and equipment do it yourself. It's likely a 5 cent capacitor that needs to be replaced. but there are very few skilled techs, most will only know how to replace an entire circuit board. So repair may not be economical, even if it's only a 5 cent part.
Nahh buddy, the presonus preamp uses a standard 12AX7 tube, 4 of which are currently residing in the preamp section of my bass head, so it definitely is relevant to a bass amp.
Wow I just actually read the user manual. Yes it's a 12AX7 and they'd really managed to shoe horn it in there.
The manual even says to replace the tube when the sound quality starts to degrade.