Not trying to be an apologist for "colourful" opinion, but he's not talking obsolescence so much as reliability. Speakers (without foam surrounds or ferrofluid) last forever. Amps, not so much. Limitation is the electrolytic capacitors, they hate heat and die. I've replaced them in my sub's amp, my Bryston amp, and my Hypex power supply already. I'm a EE and have estimated working life for electro caps at elevated temps, not pretty.
So true.
Sticking them in a cabinet with no ventilation will not improve the situation.
I encountered three types of heat exchanger designs in active studio monitors I have owned:
(A) The one you describe. Haphazard. Hot air circulates inside a boxed-out space with electronic components, heating back-wall smooth metal plate. Works for class-D amps, yet not good for the caps. No longer own any monitors with such design.
(B) A tricky one. The heating internal electronic parts are exposed to room air via the cabinet port(s). Designer's hope is that the monitor will be getting enough low frequency signal components, so that the air being pumped through the ports will be cooling the electronics well enough. All or almost all Adams are designed that way (don't know specifics of their largest monitors designs).
If the designer's assumption holds, all is good. However, if the monitor spends significant time being turned on but without signal, or if a separate subwoofer is utilized for low frequency signal components, the assumption breaks down and the caps may overheat. I believe this is one of the major reasons for Adams not having a stellar reputation for long-term reliability.
(C) What I consider to be a proper design. Utilizing metal heat exchangers connected to a conventional large finned radiator at the back of a monitor, or the whole monitor cabinet being one large metal heat exchanger combined with radiator. Genelec and Neumann favor this design approach. Shall be about as reliable as a conventional amp. Had no failures with those so far.
What magnifies this several fold are the crap caps that sometimes come from China these days. They took out my Hypex and sub amp.
Yep, instead of the proper 10,000+ hours of useful life under nominal voltage and ripple, such caps may only provide 2,000. The tell-tale characteristic is factory warranty duration. Avoid "professional" studio monitors with 12 months warranty. Real professional monitors tend to have 5 years warranty.
