How would I know if my amp needed re-capping?

OK so I got this Onix OA21 off ebay... its obviously quite an old amp, could well be up to 20 years old in theory... and theres no indication as to whether its been re-capped recently or not.

So how would I know?

The amp sounds pretty good to me, but I feel its bass is a little weak compared to my old Rotel (but maybe thats just the character of the amp itself?).

Who could do it, and what sort of cost would I be looked at? (i'm no good at DIY)... is it a time consuming job?

Is it worthwhile to get higher quality caps than the standard one... is there a big difference in quality?

Thanks for helping a DIY numpty.

 

Anything over 10 -15 years old in my opinion will need recapping...

pm me

Cost, a lot depends on whats in it and who you get to do it.

Yes no maybe ....how long is a peice of string ?

Better caps will help even if you just up the spec from 85degree to 105 degree.

But if your going to the trouble of recapping you want to fit the best your budget will allow.

tell us whats in it !

 

Weak in the bass compared to rotel? Hmmm.... Last rotel I measured rolled off from 100Hz downwards (about -2dB at 20Hz). It certainly sounded lean compared to amps that are flat to 20Hz.

Recapping... electrolytic caps don't last forever. If you're not averse to taking the lid off, have a look at them. See if the tops are swollen or there's any sign of leakage around the bases. Given its age, I would think that recapping would be on the agenda.

As for what to use, depends on how much you're prepared to spend. For analogue, Samwhas and Panasonic FCs aren't too expensive and work well. Spend a bit more and you can get into Elna RJH, Rubycon ZL and ZA. Above that there's Elna Stargets, Cerafines and Silmics, Rubycon/Jelmax Black Gates (if you can find them and afford... Rubycon produced them on behalf of Jelmax Corp, but recently stopped) and of course the real esoteric stuff.

 

By checking if it is much more than 3 years old and....

.....contains electrolytic capacitors.

If there is notable dust on a cap it is old.

You?

If I had time I'd probably charge £ 35/Hour and parts. Given that usually a few dozend capacitors exist per channel and old Naim, Onix etc Amp's are a bitch to disassemble and reassemble expect a good few hours.

It MAY be worth to upgrade, but "upgraded" rather than standard capacitors may change a well balanced sound to one that is no longer balanced.

Ciao T