Heatsinks for Aleph 5

[tobias_svensk]

I´m thinking of buildning an Aleph 5 in a couple of months.

And I was thinking of buying 2 heatsinks from Conrad Heatsinks.

Would one MF35-151.5 be enough for one channel? (0.21 C/W)

I have seen 2 calculations: (this for 150W/channel and 23°C amb.temp.)

C/W x W + amb.temp. = 0.21 x 150W + 23 = 54.5°C

Or some formula at Conrad, with some correction factor K: (calculated for 30°C rise above ambient, K=1.33)

30/(1.33 x 0.21) = 107.4 W power dissipation.

for 150W there would be:

40/(1.24 x 0.21) = 153.6 W power dissipation.

In this case the heatsink temp. would be 40 + 23 = 63°C

Someone know wich one of these is the most likely?

And the transistors would be spread out over the heatsink...

Thanks

[dantwomey]

Have a look at Mark Finnis' Aleph 5. He uses similar heatsinks and hopefully his experiences will be a good guide for you.

Regards,
Dan

[tobias_svensk]

Oh thanks that helped!

Cheers