life span/failure rate of filter capacitors?


(And I assume that the filter caps are the large electrolytic caps with the screw in terminals?)

The reason I am inquiring about this subject is that I stumbled on to an older thread started by someone who had a "filter cap explode" inside his 20 year old Cary V-12 monoblock.  (Which is basically what I have, only mine is a single stereo amp.)

Anyway, I do know the specs on those large caps with the screw in terminals which I am thinking are aka filter caps are 560uf 400v. 

Do these normally give any kind of warning before they let go?  It does occasionally blow the 3A SB AC power fuse on start up. 

TIA for any information/advice on this subject.

immatthewj

Thanks for the reply, @sns , I remember (and miss) the Dennis Had days. There used to be a wonderful individual (Kirk Owens) in tech support who was quite patient and thorough and walked me through about every problem or upgrade I ever had with one of my CAD products.  I am thinking that Dennis is probably as busy as he wants to be with his Inspire line of SET amps and his preamps. 

Is it your opinion, then, that I should go ahead & replace those 21 year old caps?

If it were my amp I'd do it, minimally it will allay your doubts in regard to their possible failure, and if you're keeping amp for the long term they'll have to be replaced at some point.

Thanks, @sns  , I would like this amp to last longer than I do, if that is possible.

I just got done looking on partsconnexion, & this may not be as easy as I was thinking it would be (finding one with the specs I want).  I'll do a search on the others you mentioned--Mouser, Allied.

If worst comes to worst, I guess I can email Cary & try to buy four of them there.  Back in the 90's I bought a "power-bank kit" (added filter caps and an umbilical cord to attach them with) for another Cary amp I had, and I am going to look, but I am thinking that they were the same value.  Cary's prices for signal caps are crazy, though, and I suspect they would be for filter caps also. 

Regardless, thanks, & I'll look at those other places you listed.

Depends on a lot of variables, size of the capacitor (larger caps don't get hot as quickly as small caps) if it's placed near hot areas of the amp and quality of the capacitor. Most of the really large caps of high quality usually last a lot longer than all the smaller caps in an amp.

Eric has provided good advice.  Plus you may also begin to hear fluctuations in the music with power capacitors.  If you are in the NYC area I can take a look at your unit.  On Parts Connexion look for Nichicon Super Through parts.  You can go up in value if you have to just make sure that they fit in the space you unit has.