Older PURE CLASS-A Amplifiers

Is it necessary to change the caps after many years of intensive use on a Classe Audio DR3B?

Is it necessary? No, unless you're having audible problems (muddy, veiled, undetailed sound).

Electrolytic caps deteriorate with time & heat & other factors -- a major factor being non-usage. You have used your amp, so deterioration is less than in other cases.

Replace with caps of same value -- or even adding coupling caps... BUT leave this stuff to a qualified tech.

Look for the rare Pass Labs Aleph 0s (40W pure Class A)stereo power amplifier. This was one of the most natural sounding power amps I have ever heard. I am always looking for one ever since I heard the Pass Aleph 0s years ago. By the way the Pass Aleph 0s is one of Nelson Pass's favorite amp of all time. I talked with him for about an hour one day and he told me if you can find a Aleph 0s make sure you grab it.

I second the Classe DR-3B. A friend of mine had one for a short while and I told him to never sell it. It was one of THE best amps I have ever heard IMO. His speakers were relatively ineffiecient so he sold it. I couldn't swing owning it at the time.

Krell KSA-100MKII - one of the best balanced and mid ranged voiced amplifiers of all time. Caveat- You must send it in to be serviced every 15 or 20 years! Power supply caps need to be changed as they dry out - degrading sound & bass performance. Highly recommended - if you can find one.

Bedini 25/25. If you can find one, buy a lottery ticket the same day. The 25/25 continues to astonish me!