Problem With Mesa Studio Preamp

[HeavyMetal69]

I'm having a problem with my studio preamp making a ton of whitenoise on the lead channel. It'll also randomly crackle and pop.

It's been this way for a while...maybe there's a way to quiet it down? Besides a Hush

[Enzo]

Try new tubes. If that doesn't get it, you most likely have a noisy resistor.

[Chuck H]

I'll second that with a caveate... A noisy preamp tube IS the most likely problem. But...

I had a Studio Preamp for a few years when I was starting to learn about amps. I remember it WAS a very hissy thing and replacing the plate resistors did help. I also replaced the "bright" switch with a pot because although the amp was too dull without it engaged, I would flip the switch and PSSSSSSSSS!!! Instant ton 'O' hiss. A 25k pot allowed me to get a bright enough setting without too much extra noise.

Those amps are really convoluted inside. With an onboard reverb and the graphic EQ and all inside. I wouldn't expect really quiet operation.

It could have been the heater voltages or something but mine seemed to go through preamp tubes pretty fast. The amp started sounding ratty after only a month or so if I didn't feed it new preamp tubes. It could have been the crappy chinese tubes that were common at the time too. I didn't know much better then. It was a long time ago.

FWIW I understand that Metallica and Queensryche both used the Studio Preamp for many recordings. I liked mine pretty well other than the above mentioned difficulties.

Chuck