Output Devices !

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With 25V secondaries, you'd end up with 32-33 volts after rectification/caps. You could safely bias it to 3-4 amps, but you'd have to make sure you can dissipate the heat. 4 amp bias@32V with 8 outputs, would give you roughly 260watts dissipation, and well in the safety range for fet reliability (depends on the heatsinking). 50w@8ohm, 100w@4ohm. Brians main amp board would be fine, but you'd have to P2P the output stage. If you give us the dimensions of your heatsinks that would narrow it down a bit.


-john


or you could just 'go for it' as the man says (he knows what he's talkin bout)
 
I have 2 heatsinks each one is 1.375" tall w/1.0" fins spaced roughly 0.25" apart ! The length is 17.0" and the hieght is 8.0" Also I had planed on using the BrianGT output pcb's ! Being designed for 3 devices each my plan was to omit the center device. Again hoping for better spacing and less heat ! The sinks in question un-painted or anodized, they were purchased from surplus ect.... If they are not large enought please point me in a direction for something more ideal ! Also if the heatsinks were to be used at say a 45 degree angle as aposed to 90 would this help to improve there effiency ?????
 
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You would probably want to limit bias to 3 amps, for 190watts dissipation per channel. The sinks are big, but the fin height may be the limitation here, you'd probably be alright, just keep an eye on fet temps. Build it, test it, rebuild if necessary.
 
Being fan assisted and at a 45 degree angle would this help enough to run at a 4.0 bias point ? Picture a triangle shaped enclosure with the top chopped off. Now with some portion of the top being flat mounting a couple fans to cool the interior as well as assisting the sinks, would not the draw be enough to improve cooling ect....
 
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