Have you actually done this with a big amp? The thought has occurred to me as my XL-280 gets toasty after pushing my RS-II's for a while. I'd like to hear a success story before I put down the bucks for the laptop cooler.
And to the OP: Well done. An excellent, almost unbelievable scroe!
Thanks for asking - Personally, no, it was just an ADD off the cuff suggestion. I have experimented with Whisper and Whisper XL fans (have a bunch of them) for cooling tube amps and power amps in racks and enclosed spaces, but that is more about getting cooling air moving in areas which tend to get stagnant.
If its true that most of these amps were designed with convection cooling, then improving or increasing air access and airflow rates can give a better reserve on thermal management. You'll note that many big amps have their cooling fins exposed. Many amps enclose their heat sinks but provide for fans to move air within the case.
In this amp, you can see there is a lot of venting on the cover, and hopefully similar venting on the bottom to allow air in. If the recommendation of getting the amp up by 1, 2, or 3 inches helps airflow passively, then an active air source, even at low speeds, properly situated and flowing into the air passages would be even better.
However, you never get something for nothing - if the active fans fail or stop, then the device may actually impede normal convection airflow, so that's a potential problem. You would also need additional space for the fan device and unobstructed air flow to it for it to work well. Finally, there is the issue of noise from the fan systems, and many laptop fan cooling systems use the same small (80 to 120mm) fans found commonly inside regular towers. These tend to spin at speeds which can generate noise or are run slower and quieter with some resulting loss of airflow. That's why I've always rather used larger fans with slower spin speeds to try to minimize the fan noise.
The other issue is can a laptop cooler tolerate the weight of an amp like this if simply placing the amp on top is the option? Or do you need to raise the amp anyway, and then attach the cooler but without weight bearing?
All these questions are part of any DIY type solution.
