I've grown to expect old capacitors in 1940's tube radios are usually bad, so I replace them right off the bat. But I guess I kind of expected modern paper-in-oil caps would last a little longer. Is that not the case? Do they all tend to dry up and become resistors? That's what happened here, the dielectric began to break down, and the plate-to-plate resistance dropped, allowing more and more DC current to flow. Is this the case with all paper-in-oil caps? Mine only lasted five years.

This is from dim memory (at least a day or two old), and high on rumor
quotient, but I think someone mentioned that AN labeled PIO caps were,
at least some of the time from Jensen and not long-lived. Others last a
long time.

Skip

However, this is still good information. I'll try some new PIO caps and see how they last.

Norris

Kimbers were an improvement over the Auricaps, slightly, and the copper case Obbligatos take home the prize.

• Obbligato

I have had quite a few of those Audio Note copper PIO's short out in my gear too. Peter Q over at AN has admitted that there are some issues with those caps. The film that separates the dielectric is the problem. It breaks down eventually causing the cap to short out. Peter has redesigned the copper PIO's using a mylar divider that is supposed to be good for a long long time. Peter has agreed to take back any shorted out copper PIO's and exchange them for the new mylar coppers free of charge no questions asked. I know you have coppers in that kit 2, because I put them in myself. The coppers really are what sounds best in that amp, I would take Peter up on his offer to exchange the shorted ones. The new ones will have white lettering on them. the old ones had black. Also I would check all the coupling caps and cathode bypass caps in there. You should get no more than a few volts across any of the signal caps. If you're getting high readings like in the 80+ volt range, then they are getting ready to go. Replace any that you find like that immediately.

Mark