The mounting is made to work with the UMS. If you remember in each kit there is a gainstage board for 2 ch that can be snapped in half, and 2 N ch boards, each with 2 MOSFETS and 2 diodes and 2 P ch boards each with 2 MOSFETS and 2 diodes.
-One kit spreads things out well for 2 ch (each with a P and an N output bd so 4 output MOSFETS per channel, 8 total) in the 5U x 400 chassis.
-One kit can use half the gain bd. and just one N board on one side and one P on the other in a 4U x 300 chassis as a monoblock. So one kit gives 2 smaller monoblocks each with 4 MOSFETS
-Two kits could make 2 monoblock 5U x 400 chassis' each with 2 P and 2 N output bds so 8 output MOSFETS per channel, total of 16 MOSFETS in two 5U x 400 chassis.
As far as diameter of pads on traces, well whatever Alex did...
-One kit spreads things out well for 2 ch (each with a P and an N output bd so 4 output MOSFETS per channel, 8 total) in the 5U x 400 chassis.
-One kit can use half the gain bd. and just one N board on one side and one P on the other in a 4U x 300 chassis as a monoblock. So one kit gives 2 smaller monoblocks each with 4 MOSFETS
-Two kits could make 2 monoblock 5U x 400 chassis' each with 2 P and 2 N output bds so 8 output MOSFETS per channel, total of 16 MOSFETS in two 5U x 400 chassis.
As far as diameter of pads on traces, well whatever Alex did...
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Cool Variac! Can't wait !
I know someone here probably asked already, but is it relatively easy to convert it to a balanced system by crossing a few grounds?
I know someone here probably asked already, but is it relatively easy to convert it to a balanced system by crossing a few grounds?
in theory it is🙂
but that is all it is yet. and it will be a heck of a powerplant.
4 pair input J-fets. 16 pairs of outputs. and +/- 55-60V and you got a 300W class A amp😀😀
acctualy. you can rach the 500W class A mark at 8ohm😀
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Balanced is best wayy to get votage up without raising rails, taking advantage of available current.
yes. if you can get it working right🙂 and have current from hell and above. same with outputs. and maybe input J-fets🙂
ok ok, I was just daydreaming about a balanced version.... have no real aspirations for it anymore. 😱
Standard 4pr version it is, I think its enough power already 😀 and plenty quiet if it mimics the regular F5.
AudioSan, what are your source resistor values? With the rails that you have, if you run 3A bias you should be able to get close to 150W.
If you use 0r47 then overall, V=IR your total bias voltage should be 1.41V right?
Then each FET should run at only 0.35V bias.
Standard 4pr version it is, I think its enough power already 😀 and plenty quiet if it mimics the regular F5.
AudioSan, what are your source resistor values? With the rails that you have, if you run 3A bias you should be able to get close to 150W.
If you use 0r47 then overall, V=IR your total bias voltage should be 1.41V right?
Then each FET should run at only 0.35V bias.
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it is not to scear you🙂 it is possible. just do it right🙂
about bias. that will be 2.5A. so 0.62-0.63A pr output. and i'm gonna run dual 1ohm 5W pr device. so 0.32V drop🙂
i'd like to run higher bias. but with rail voltage of +/-50V the sinks can not handle more then 2.5A i think🙂 i will have a little more power in class A/B doh.
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This is why I'm going for the bigger heat sinks. If there are only 2pr per sink (sort of like the regular F5). 3A bias, or about 0.38V (0.5ohm) should be no problem 😀 in fact, going into FAB territory, bias it all the way to 0.6V per FET or 4.8A bias should be ok 😀😀.
If you are runnning diodes, I would suggest against .600mV. 50V rails and 1A bias per fet is all i would push these things, personally. With a V3, you are burning 200W per sink. That is BIG heat, although twp per Heatsink USA 10.08 @ 8" Tall should handle it. If you want to push 1.2A through each fet, you need to lower the Rs value to .33(1R ll .47R). THis will give you a Vdrop of about 400mV, keeping you in reasonable territory for the diodes and still getting you the wanted current.
Make sure you got excellent ventilation in your case.
Make sure you got excellent ventilation in your case.
wow. diodes starts conducting at about 0.9-1A you must have the bias pr device below that.
Whoops checked some calculations. forgot to factor in that it running at 50V rails.... It will need some massive heatsinks for something like that at 4.8A
Yes Buzz 0.33R would work much better.
Yes Buzz 0.33R would work much better.