too much crosstalk??

[EETStudent]

Im having some noise issues in one of my builds, and I cant figure out why. Pretty sure its in the preamp. Did the whole pulling tube things and the hiss/noise went away with the PI tube gone. When Im poking around, its like there is a small microphone attached to the end of my pliers, and everything I tap gets amplified. Jiggling wires and tapping the chassis especially. If I squeeze the pliers over the input jack wire I can hear the springs going back and forth. I THINK its the input jack. Im running a long wire(about 6 inches, teflon covered). I just hate this hiss/noise!

[EETStudent]

just throwin it out there, pulling the input tube eliminates the noise, so it must be before the actual stage, correct?

[Steve Conner]

I'd say it's more likely to be the input tube itself. All tubes generate noise and microphonics to some extent, but some are worse than others. They can rustle, crackle and pop, ring like a bell when you tap them, and even cause feedback in a combo. Try swapping a few into the input position to see if you can find a quieter one.

Also if you're troubled by hum, check your heater supply is properly balanced to ground by a center tap, two resistors or even a hum balance pot. The hum balance pot makes a worthwhile difference in a high-gain amp, IMO. My high-gain amp hisses when the volume and gain are cranked, but I can get rid of hum completely by messing with the hum balance pot.