Heatsink for DLH Amp

Do you think this is enough heatsink for two DLH amps? I think I pulled it off of a powered sub so not new and no spec's. ( No idea why it flipped the picts ).
 

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The wattage it puts out doesn’t matter. Just look at the notes for the voltage and bias current. It’s +/-15.6v, call it +/-16v. 2 amps.

That’s power = current x voltage.

Watts of dissipation into heatsink = 16v x 2 x 2A = 64W. That’s about what a 4U x 300mm Class A heatsink on the typical DIY store chassis can do per side.

If you find a heatsink with a dissipation rating say, 0.55C/W. Take 64W x 0.55C/W = 35C rise. Add that to ambient temp, say 22C for typical N American home w AC and you get 57C. Which is just a tad above the usual 55C “acceptable” norm. That’s basically the temp where you feel like it can burn you if you hold it for more than a few seconds.
 
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Thanks X. Ya know, I feel a little embarrassed. I know about power dissipation and I completely ignored it. You even pointed it out in your first response of this thread. Your answer smacked me in the head and said wake up. This down time has got me messed up. Again, thanks for the explanation.
 
Hi Ripcord,
No need to feel embarrassed and did not mean to make you feel that. Just explaining the way to estimate your heatsink requirements. Yes, the SLB is perfect for this application. If you want 16v, you need to account for 3v drop in SLB cap multiplier and about 3v or so sag in trafo under a Class A load. Assuming you go with dual mono setup and Antek I would size it 3x rated capacity. So 3x64W is about 200VA. And need 16v plus 3v drop plus 3v sag for 22vdc no load. 22v/1.41 = about 16v. Given a choice of 15v or 18v. Depending on your heatsink go 18v if a big heatsink and 15v if smaller.