Tubegroover...A slight correction..I am not "hung up" about high distortion as you might note from my remark:
"I know that distortion specs are not the whole story, but when THD gets over 1 percent it becomes a big obstacle to overcome by other virtues".
I think that this comment is pretty reasonable.
Regarding degradation of electronic components in tube power amps...back when I was involved with repairing/tweeking these things it was "standard operating procedure" to go through and replace all the interstage coupling capacitors every time you worked on it. I never asked why, but such customs are usually based on experience.
I just observed another thread where MacIntosh amp characteristics, considered good, were attributed to use of output transformers (even though the circuit is solid state). And here we have ingenious circuitry designed to avoid the use of a transformer in a tube circuit. Go figure!!
"I know that distortion specs are not the whole story, but when THD gets over 1 percent it becomes a big obstacle to overcome by other virtues".
I think that this comment is pretty reasonable.
Regarding degradation of electronic components in tube power amps...back when I was involved with repairing/tweeking these things it was "standard operating procedure" to go through and replace all the interstage coupling capacitors every time you worked on it. I never asked why, but such customs are usually based on experience.
I just observed another thread where MacIntosh amp characteristics, considered good, were attributed to use of output transformers (even though the circuit is solid state). And here we have ingenious circuitry designed to avoid the use of a transformer in a tube circuit. Go figure!!