I have here a music man 65 reverb amp head (2275-65) with a very quiet and fizzy, distorted output. Brand new EL34s & Capacitors have been replaced but problem still persists.
Here’s where things get strange however, the amp seems to work well when i remove the op amp chip (1458). Volume jumps up and i get a very clean crisp signal. But if i put the op amp back in, it’s back to low fizziness. I figured the op amp was fried so i bought a new one, and installed it, but the new one is behaving the same as the old one!
Does anybody know what’s causing this? or how I can fix this? Please and thank you!