Biggest Complementary Transistors

[EWorkshop1708]

Depending on how hot they get IMO determines if you need a fan or not.

I've gotten one of these sinks somewhat-hot with an 80W TEC to test, and it does just fine without a fan, but a fan makes a huge difference, and hardly gets warm. These heatsinks to me look like they were meant to be fan cooled because the fins are close together.

I've used fans on heatsinks in an amp that are meant just for convection cooling, with a bit wider fin spacing, and the fans always make a significant difference. A little wasted air IMO isn't a big deal.

Now for the amp I'm building, I'm using regular NJL/MJL4281/4302's, however, if I build a large power supply, amp, or whatever, I'd like to mount some monster transistors with the other sinks I have.

[megajocke]

Originally posted by AndrewT
Jacco,
you seem very sure, but I disagree.
The sink will waste too much forced air in those big gaps.

I agree that it would be possible to have more fins in there if using it for fan cooling but that would need more material - if it's good enough for the intended application why make it heavier and more expensive?