Dual Rec. Noise/Hum Ch. 2 & 3

[phatalbert]

My 04 Dual Rec. 3 channel has recently started making a lot more noise on channel 2 and channel 3. It's a sort of like a hum noise. It's most noticable when not playing. In between songs in practice/shows I have to switch to my clean channel 1 so we hear each other talking. It sort of sounds like a bad ground within in the amp...is that possible? I checked out all my guitar cables/speaker cable and they work fine in other amps. The clean channel 1 is fine though. I recently re-tubed the whole amp with JJ's and tried putting the stock tubes back in. I also tried moving the pre-amp tubes around to see if maybe my V1 tube was causing the noise, but still no luck. Any one run into this or have any other suggestions before I bring it in to a tech?

thanks

 

[Boogiebabies]

Have you tried the lead stage preamp tubes? The V2 is not always the culprit. The lead stages on a DR take extreme voltage, up to 400 volts on the plate. If you do nopt have a decent tube in there it will chew it up. In your owners manual there is tube assignment chart. Try changing the rest of the preamp tubes. Then, if that does not work you may want to see if your power tubes are not way off. If the problem persists, check your cords, outlets etc. again.