Hello guy's , bin a while since i made any request's for asistance, but unrapped a mint Aiwa cs-j1 resently. On doing so I noticed that i had made a little note for future reference about a popping sound coming from both channels, it's been about 10 months since i last used this unit, anyway the sound goes on for about 5mins then disapears. The radio section works fine no popping, however it's the tape section that the popping sound appears on although it works properly as i mention earlier after a few mins it's gone, It does'nt seem to be getting any worse. My question is this i have a few Aiwa's that have developed the infamous capacitor problems, should i be concerned about this. This unit has been in my collection for more than 5 yrs, as has my hsp-x101 which apart from a new belt seem's fine( hope i hav'nt jinxed it). I remember replacing the belt on the cs-j1, a very time consuming job especially as i was also faced with baby sitting duties that weekend, but managed it. Should i change the caps now or later, cn't see any electrolyt leakage. 

If you suspect the electrolytic capacitors are the culprit, then the only way to know for sure is to measure them with an ESR meter. The rubber gasket over time can shrink and the electrolyte can either leak out or evaporate with little visible external signs of failure. Any capacitors that read high or off the scale are bad and will need to be replaced.

Alas, if only they were.

Digi-Key are based in USA not UK. They just have a UK centric website. You will still have to pay a lot for postage and import duty to UK when ordering.

Sure you are not confusing regular ceramic disc capacitors that don't leak with aluminium based wet electrolytic can capacitors that do?

Like Minty suggests earlier, Digi-Key is a good place to go look for capacitor parts. They seem to have the widest range by far. You could also try Farnell who are based in the UK, but they have a limited range and sometimes will charge extra for parts are located outside of UK warehouses.

But before you buy any, get an ESR meter. If you own vintage electronics like AIWA it can save you a lot of time working out if faulty capacitors are to blame. You can pay big money from the high street via Maplin for one or get a relatively cheap one from t'interweb.

The general concenus regarding tantalum caps is that they should be best avoided where possible for audio applications. However if there is an absolute need for them, then careful consideration of the tantalum to be selected should be made.

If you are worried about wet aluminium caps, then there are solid aluminium caps available nowadays which are not likely to leak.