amplifier longevity

@johnsonwu  as you know, like you I have been repairing Counterpoint components for some time now.  While it was a common practice and there for a reason, I have also seen many covers with holes so the heat does not get trapped.

While it may not be the single cause of failure, IMO and from repairing about 50 Counterpoint power amplifiers, I would suggest that the covers while providing a benefit, are not optimal for heat dissipation.

YMMV

Happy Listening.

32 year old NAK PA-7A MKII & CA-7A pre here.

Both checked out by ex NAK tech early this year. They're in A+ condition.

Caps are in great shape, and tech says you couldn't buy better ones even now no matter what you spent.

      Here’s my 2 cents , based on my experience.   First heat is the enemy, all amplifiers need proper ventilation. I’ve added fans to setups that generate high heat. Tubes are a wear item , especially power tubes and degrade over time. So you WILL be replacing tubes over time. I’ve had a tube failure that caused the glass envelope to crack, but no additional damage. I’ve had a new power tube fail that resulted in internal damage and required Dennis Had to rebuild the power supply section. I also own Rogue and have seen LCD screens fail and circuit boards fail. Also consider some tube amps are point to point and some use printed circuits. Overall SS is more reliable and significantly less effort to maintain.  However I personally enjoy the TUBE sound and I’m willing to deal with the maintenance issues. In my opinion comparing tube to SS, but s like comparing Ducati to Yamaha. I believe that audio, like motorcycles is most appreciated when we experience as many different styles as possible. And FWIW I just sold my Buell and my HD due to age. Happy Listening, Mike B.

The best valve amps with point to point wiring are more reliable and long-lived than anything solid state. Except every once in a while over time one of the valves can spring a leak.

Yep, heat is the biggest enemy. Point to point wiring and greater spaciousness a good thing, best quality parts with higher heat ratings and cooling with fans helpful. Inrush current is in fact a concern with tube amps, my 845 SET with nearly 1000V has huge caps to charge up, this is major wear and tear. Point is be judicious with turning tube amps on and off.