Swap the tubes, one channel for the other, one tube position at a time, to identify whether the problem follows an individual tube. (If the symptom is only intermittent this may have to be done over a matter of days.) I would start with the input tubes first.
KT88 Monoblock amp makes a spitting sound at times
I have a pair of Quad II Forty monoblock amps. Was thinking of selling them, to go the low power SET route, but would have to get more efficient speakers. So thats been shelved as money is an issue . Anyhow they sound great when they aren't acting up.
Having said that , one has started to make an occasional spitting, kind of phono stylus touched by finger sound once warm. Only after warm and only sometimes. Is this symptom of some kind of imenent failure?
The other was making a mild hum,remedied at first by applying light pressure to the top of tube cage. Opened it up and looked for some sign of a bad wire route etc. but has since stopped mystriously. .Any ideas as to this one ?
Have been planning to put fresh KT88's in and perhaps new rectifier tubes, 5U4G in both just to be sure.
Kind of new to the whole tube thing, but happy when the amps follow suit. Any suggestions welcome. Types of tubes and fixes.
Having said that , one has started to make an occasional spitting, kind of phono stylus touched by finger sound once warm. Only after warm and only sometimes. Is this symptom of some kind of imenent failure?
The other was making a mild hum,remedied at first by applying light pressure to the top of tube cage. Opened it up and looked for some sign of a bad wire route etc. but has since stopped mystriously. .Any ideas as to this one ?
Have been planning to put fresh KT88's in and perhaps new rectifier tubes, 5U4G in both just to be sure.
Kind of new to the whole tube thing, but happy when the amps follow suit. Any suggestions welcome. Types of tubes and fixes.