amplifier longevity

Many companies are now putting them on the back of the unit. If you are not going to be using it for an extended period of time,they should be turned off from an electrical safety standpoint.

some very low current preamps or phono stages dont have power switches.

My Pass Labs Alepth 1.2 Class A monos have two decades on them now. The filtering or power supply caps are the soda can electrolytic type caps; I’ve seen the moniker computer power supply caps used to describe these large caps with terminals on the top. I’d love to see if replacing those old style caps with modern low ESR say polypropylene and foil film caps or something like that would bring about an improvement.... That is just conjecture on my part; I should just leave it to Nelson, the true expert, to upgrade because if anyone would know, it’d be the man himself, Nelson Pass. The great thing also, he is within driving distance of me so I don’t have to ship my gear and let the UPS fellas beat up my stuff!

You just made me think...My Rowland Model 12 monoblocks have been problem free since 2009 installation. And they get workouts!

Heat, depending on design and how and where is used, can defiantly pose a longevity problem.

Early model Krell KSA and KST power amps notoriously failed do to cap failure from heat. Design modifications using better caps and more attention to heat dispersion solved the problem. I know of the problem with the Krells because I had them and went through the headache and expense of getting problem solved.

Not to pick on Krell, per say, as am sure that other early hi-biasing class A/AB amp manufactures had heat issues to work out as well......Jim

Like @rbyington711 said, Pass Labs, particularly X350.5. They are built like s tank and sound like top-notch tube amps. Their electrolytic capacitors are lasting >20 years. I went from Pass X250.5>X250.8>X350.5. Each time I am amazed how good they sound.