early 70s 504

[Roe]

I had a 1972 504 on my bench today. sounded great with original caps (but without original tubes). I guess the caps will have to be changed sometime but I dont feel like changing more than necessary

[mhuss]

I just check for excessive "bulge factor" on the the cap seals. I have a '70 I still haven't recapped, but I don't gig with it, so I'm not as worried about reliability.

--mark

[Roe]

no bulges at all. and she sound powerful and isn't noisy. owner hadn't though about caps at all. he was worried about tubes but these were good

[OldSchoolDave]

no bulges at all. and she sound powerful and isn't noisy.

In that case, I wouldn't change anything, either.

So - what do you suppose accelerates cap failure? Use? Lack of use? Wide temperature swings?

Dave

[Roe]

the way to kill caps is to leave them unused for years and then hit them with massive voltage without any prior forming.