Heat

Theoretical, or actual amp in an attic? Summer attic temperatures are like this

https://www.youtube.com/watch?v=EhZba-P7R18

Pushing hot air at a hot thing ain’t gonna do much. Attic exhaust fans can avoid extreme temperatures, but not enough IMO.

A box with small personal ac unit can work, however, power on/off, settings, and importantly condensation needs to be dealt with.

Some floor standing room units have ducts to vents like a clothes dryer, that would work if that could be worked, again, an enclosure to retain the cooler/block the hotter air would be wise. I used one of them to cool the V Berth in a boat in Florida I inherited (thankfully sold) found one with self evaporation, pvc pipe for heat exhaust.

Very simply, the operating temperature of electrical equipment is X deg F above whatever is the ambient w/o forced cooling such as a fan.  If X deg F is say 25F, and the ambient temperature is 75F, the internal operating temp is then 25F + 75F = 100F.  If the attic reaches 95F, the equipment operating temp increases to 25F + 95F = 120F.  In reality,  X deg F above whatever is the ambient is somewhat variable for the static condition, but for the range we are generally talking about its relatively constant. 

As @millercarbon has detailed, forced air can increase the heat transfer lowering the equipment internal operating temp.  But for forced air to lower the equipment operating temp (to remove heat) there has to be a temperature difference - the ambient air temp has to be less than the equipment internal operating temp (or the external heat sinks).

The easiest example for what happens at elevated operating temps is to look at a capacitor.  The average capacitor in home audio equipment is rated for an operating temp of 85C (185F) for 1000-hrs.  For every 10C(18F) less that it operates, the service life doubles.  So, operate at 75C, the life is ~2000hrs.  Operate at 65C, the life is ~4000hrs, and so-on.  But, operate at 95C and the life drops in half to ~500hrs.  

Quick examples:  If in a 25C(77F) room & an equipment operating temp of 40C (104F), the service life of the 85C/1000-hr capacitor is ~22,000-hrs.  In an attic at 35C (95F), and an equipment internal operating temp of 50C (122F), the service life of the  85C/1000-hr capacitor is now only ~11,000-hrs.

Some of the better audio capacitors such as  Mundorf are rated 105C while Teflon capacitors are generally rated 125C. Industrial power capacitors may be rated 85C/10,000-hrs - they are designed for 30-yrs continuous service.  

antinn, thank you. I believe all of my capacitors are Vishay and that’s as much as I know. Anyway, I’m thinking that I’m safe in the attic as long as I stay away from playing time during the hot season. Because of the hardwood floors, it is very dry up there which is also good for my electrostatic speakers and in the fall and winter, it stays very cool.

Dear friends : ""  Heat is the enemy of audio equipment. "" and I can add: operation out of the limits of the source of electrical power.

Now, every decent amplifier designer/manufacturer takes in count those both parameter in his design overall/main targets and his calculations on the design takes in count both parameters.

So if the amplifier is well designed no one needs any " crazy fan " even in the attic due that not only because the well designed unit but because that good engineering designer already designed his unit with a thermal protection and to electrical protection too.

Look, I own two Levinson 20.6 monobloks and in my country ( México. ) people have air conditioners only in those country places where temperature goes as high 50° C but in zones where as my place that does not happens we in reality do'nt use even with temperatures at 35°C.

In the winter and in the cooler days that normally never gone below 0°C the pure Class A 20.6 puts as warmer ( heatsinks and all the amplifier external metal surfaces. ) as in summer. Difference is that during the winter the time to get hot is a little longer.

Yes, those amps does not puts warmer but hot really hot, you can't touch its external heatsinks even the face plate and the handles are warm enough.

Guess what? no matters what the amps never switched to its thermal protection circuit. The 20.6 has not internal fan and its electrolithics filtering caps are rated at 95°C by Sprega that today is member of Vishat group and the Wima caps used in the circuits are rated at 105°C.

The design is all about, period.

Those amps came around 1987-1989 and never failed in any way:

https://worldradiohistory.com/Archive-All-Audio/Archive-Audio/80s/Audio-1987-08.pdf

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.

A fan can add  dirt, noise or grunge to the electric line and make the sound bad. Make sure it is not plugged into any sockets or lines that the system is on.