Filter Cap Age: When to replace?

[speakerguy79]

I have an Adcom 555mkII that I'm guessing is about 15 years old. Is it time to start thinking about replacing the filter caps? I know electrolytics have a lifespan but I'm not sure what it generally is (20yrs?). Also if anyone knows a good replacement part # for the 555mkII I would appreciate it. Thanks!

[AMV8]

Hi
I am not familiar with your speaker however I believe that you are right to think about replacing the caps in the filter after 10 years or 10,000hours use.
I am also not sure of your background in audio so I will start form the beginning and you can skip a lot of this if you already know it.
Generally you only need to replace electrolytic capacitors in the filter. Resistors and coils will be functioning ok and will not need to be replaced.
The electrolytic capacitors should all be replaced by new bipolar electrolytic capacitors. However if there are any electrolytic capacitors in the treble section of the filter these should be replaced with plastic film capacitors- polypropylene (MKP)or polyester (MKT)- the latter being a bit cheaper.
Digikey and Mouser sell the parts you need.
I hope this helps. If you need more info you can e mail me.
Don

[Sonusthree]

Originally posted by AMV8
Hi
........ I believe that you are right to think about replacing the caps in the filter after 10 years or 10,000hours use.
...............

Totally agree Don, But, I believe Speakerguy is referring to his amp.

I'm not familiar with this model but you should definitely be considering replacement after 15 Years!!
I'm in the same situation with my Cyrus at the moment (~15 Years).
The large filter caps are the most expensive so I have started with the other electrolytics elsewhere in the amp and swapping them to Polypropylene where possible.

Your amp looks like a quality piece of equipment. What parts are fitted there at the moment? You don't want to downgrade the quality if you can help it.

Might also be worthwhile reading up on bypassing those large caps with smaller film types and the contentious issue of snubbers!!

Happy Christmas everyone.
Cheers,
Martin.