used capacitor

[Starunit10]

Hello, quick question do caps (in line caps, not the caps in a amp) go bad the same as amp caps after time? Should I be looking at buying a new cap as opposed to buying a used one?

[nutxo]

The do go bad but can be tested. Hook a wire to the positive and negative of the cap. Hold the negative against a battery and tap the positive several times quickly. Then use like a flashlight bulb to discharge the cap. If it doesn't light up the bulb its dead. I " THINK" this is how I remember how to do it..... Im old. Things get mixed up in my mind :-p



Myself I wouldn't even consider one of these. Either fix the issue or get a small agm battery instead.

[Eric D]

I think it is very important for everyone to know that ALL caps (except for maybe some hybrid poly who know what modern one I am not familiar with) go bad AT SOME POINT.

The key here is just how long that is.

There are loads of 1940s or 1950s tube amps with original caps still going strong to this day.

The caps we deal with going bad in our older PG amps are due to poor manufacturing or a bad chemical recipe of the caps themselves. It is not normal in any way for caps to fail so rapidly.

Anyone into computers probably knows about the bad run of caps a few years back, resulting in countless failed motherboards, and other electronic devices. This shook the whole electronics industry much like the exploding battery problem did also a few years back.

So, caps go bad, but not nearly as quickly as what we are dealing with in older PG amps.

I have not replaced the caps in any of my other brand amps (unless they were actually damaged by other means), and I don't go around my house or dig into the computers in my vehicles to replace all the caps I can find. Few products are at risk of this problem.

[vwguy3]

Hey Eric what about this one? http://www.ebay.com/itm/Soundstream-Ref ... 500wt_1413

I read over on the DIYMA that someone was complaining about some bad caps on some of the new SS ref. amps. Over there they said that the caps he saw in his amp was bulging.

Thanks
Justin

[Eric D]

If you hook up an amp backwards, and it does not have an inline fuse, or some other form on internal reverse polarity protection, the caps will boil over and explode. This is not a problem due to poor quality caps, this is user damage.

[Starunit10]

Thanks everyboby, good info. Eric D very good explanation answered my question perfectly !

[Starunit10]

everybody