F3 Builders Thread

Official Court Jester
Joined 2003
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I'm remembering just one thing , and everything else I'm concluding from that:

4U/400 Modushop Dissipante - perfect for 80W of heat per side (sum 160W), and my OCD dictating use of Babysitter during summer months (I tend to imagine sizzling caps inside)

anyone is free to have different opinion, that's according to air quality in my neck of wood

:clown:
 
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Hi

According to the DIYaudio store, the 4U/300 comes with heatsinks each rated at 0.31 C/W
If you push 100W on these in a well ventilated enclosure you will theoretically have a temp rise of 0.31 x 100 ; 31C.
If your ambient is 25C then your heatsink will be at 56C.

Eric
Agreed absolutely. That’s just a bare minimum. I’m still curious if any builders have measured the temps at the heatsinks although it’s hard to be accurate. I bet it’s 60 degrees plus…

5U/300 it is! 0.18 degC/watt, only 18 degrees rise, and the front panel should help while having a cover on…doesn’t. I almost always add some heatsink grease between the heatsink and front panel in hopes that it participates thermally…

Best,
Anand.
 
Don't forget ratings are for heat transfer when the heatsink temperature us 85 degrees C ABOVE ambient.
You want about 25 degrees above ambient. Multiply heatsink rating by about 1.4 to get correct heat transfer characteristic.
I linked a paper on this in my Aleph 2 rebuild thread today and calculated 4U 400mm capacity.
 
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Thank you all for your input. I have some options to consider. Since my F3 won’t only be an F3, it will have a small gain stage ahead of it, either FE2022 or Wayne BA2018. I want to stick with a discrete front end, no opamp based or transformer based FE this time around, as such I will need to accommodate for that in the enclosure. It will have both balanced and unbalanced inputs. At this time, I do have one pair of Wayne’s BA2018 stereo boards (the blue ones) so I would like to put them to good use. I will obviously drop the gain on the BA2018 to the lowest it can go. The F3 on it’s own is about ~ 13dB or so.

Oh…if it isn’t obvious, I don’t have a preamp although the Iron Pre minikit just recently arrived at my doorstep :cheers: .

Thanks!

Anand.
 
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