That will not work as well, as the heat sinks will be inside the still air of the box, getting hot, and that has a much worse path to the outside.
What about just building it as designed? It was never really meant to go in an enclosure.
There's a lot of margin here, as the heatsink temperature is only a bit lower than the transistor junction temperature, and it can operate at fairly high values.
Why not? This is my next build, waiting for the FQP transistors. Bottom and Topplate perforated to enable air circulation. Compared to my first builts just 1/2 high unit
Because there’s a difference between building an enclosure around the amp and trying to force the amp into an existing enclosure.
.....which is why I laid out new boards to work properly with a little conventional chassis. It was the pricier way to go and kinda defeats the whole Mini zeitgeist ... but I really like it. It fits most rooms better than a bare board. The next build will use an ACA chassis! The blank chassis was just 20% off for Black Friday at Modushop. I've got improved boards now, too and... some Fairchilds from @KevinHeem to pop in to the next build.
I think I'm going to walk these two statements back...it is DIY after all. 😉
This is such an excellent group and the ACA Mini exemplifies engineering-type minds that optimize for maximum efficiency, while allowing for architect minds to apply self-imposed design parameters that either look cool (in their eyes) or add a feature such as implied safety. You guys are awesome.
Getting there. Mounting heatsinks to the inside with thermal paste, still have to figure out the top plate design. Compact chassis, hardest and most expensive part now figured out!
Drill holes under and above the heatsinks for airflow. They are useless without airflow.
Stating the obvious:
Heat sinks are on the exterior of a chassis for a very simple reason: to maximize heat transfer from the metal to the surrounding air by allowing the heated air to escape (rise), replaced with cooler air from the surroundings. Although 6L6's advice is always, always spot on, I'm afraid you will be impeding heat transfer if your only drill holes. I believe you'll need air flow into the fins from the sides as well as from the bottom for adequate convection.
Of course, this is DIY, so try it and let us know how it turns out. - David
Heat sinks are on the exterior of a chassis for a very simple reason: to maximize heat transfer from the metal to the surrounding air by allowing the heated air to escape (rise), replaced with cooler air from the surroundings. Although 6L6's advice is always, always spot on, I'm afraid you will be impeding heat transfer if your only drill holes. I believe you'll need air flow into the fins from the sides as well as from the bottom for adequate convection.
Of course, this is DIY, so try it and let us know how it turns out. - David
😀
Thanks! And I should say that thanks to the frame weight there is no risk that it is pulled away by large cables. Better than I hoped.