What kills capacitors is a lifetime of voltage and/or heat. Heat is caused by ripple current and ESR.
If you look at a capacitors data sheet, it will be spec'ed for a few thousand hours at rated voltage at the rated voltage and temperature. If they popped with no signs of deformation or wrapper heating, I would replace with a higher ripple current / lower ESR model, with the next highest voltage rating. If no visible problems, I would at least replace with a higher voltage C.
If it's a capacitor that's decades old, simple aging is probably enough to dry the electrolytic and degrade the cap's performance. So the folks replacing old caps as standard procedure are on the right track.
If you look at a capacitors data sheet, it will be spec'ed for a few thousand hours at rated voltage at the rated voltage and temperature. If they popped with no signs of deformation or wrapper heating, I would replace with a higher ripple current / lower ESR model, with the next highest voltage rating. If no visible problems, I would at least replace with a higher voltage C.
If it's a capacitor that's decades old, simple aging is probably enough to dry the electrolytic and degrade the cap's performance. So the folks replacing old caps as standard procedure are on the right track.
Not just SMD caps.....
some TV sets I've worked on had regular lytics that also smelled like rotten fish when being unsoldered.
Yep, it smells!
It's back again, one of those intermittent faults 
. Whilst being volume related, it only disappears at very low volume. I have two separate power supplies so I swapped them over and it went, swapped them back and it was still gone. The connectors I'm using for the power supply are Speakon. The noise is like very bad RFI, could it be the rectifiers?
. Whilst being volume related, it only disappears at very low volume. I have two separate power supplies so I swapped them over and it went, swapped them back and it was still gone. The connectors I'm using for the power supply are Speakon. The noise is like very bad RFI, could it be the rectifiers?
I would doubt it tbh... which doesn't mean its impossible... but it would be something I've never encountered.
Rectifiers in power supplies (as opposed to small signal diodes) tend to either work normally or go either short circuit or go severely leaky so that they draw so much reverse current they just overheat and fail short anyway.
Rectifiers in power supplies (as opposed to small signal diodes) tend to either work normally or go either short circuit or go severely leaky so that they draw so much reverse current they just overheat and fail short anyway.
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