Chosen Solution
Fender Twin Reverb (re-issue) clean (or normal) channel not working. All tubes have been replaced - to no avail….what do I check or need to repair/replace?
If I recall correctly, both inputs feed op amp circuits (4558 ICs I think). I would check those first. I have seen these fail relatively commonly. This will involve removing the unit from the cabinet. Follow the circuit from the input jack to locate the IC. It should be an 8-pin IC with the number 4558 on it. Update this with any progress you make. Dan
