F5 power amplifier

Hello together, i use in my f5 lsj74 and lsk170, but I am not sure that pin assigment with originals of TOSHIBA 2sj74 and 2sk170 ithe same. Could you help me, please. That the mistakes can be too expensive. Thank you.

Same, I have used both Toshiba and LSK in many projects interchangeably without worrying about pinout after verifying on first project using LSK.
 
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I ordered boards to build the F5 without the current limiting circuit and if possible match the output mosfets where no source resistors are necessary. My question is if there is a way to set the bias without the source resistors installed. I think a small value resistor on the mains would work but I have no idea what volt, amp to shoot for.
 
Fired up the F5 but did install .47 resistors but not the current limiting circuit. It is installed on big heatsinks and with .59V bias is running 25C. How high have others biased this amplifier? This is just a project so I am going to turn it up but am just curious how high the other FAB have biased their build. I will turn up till it reaches 55C on the heatsinks close to the mosfets.
 
... just curious how high the other FAB have biased their build. ...
Find a cozy place of your own somewhere between
... As a first step I switched the power transformer to 20V secondaries and had rails with 24V-ish voltage, still with the Aleph J. Set bias to 2.0 amps, so roughly 48W per MOSFET, which still worked with my heatsinks....
and here.
I'm not Fearless Amplifier Builder , as Papa certainly is ..... and I'm anyway used to make unnecessary changes to his circuits , so some trace cuttin' and one additional resistor , change of trimpot value , multiturn just because I'm Chicken :D
And never forget the master FAB principle by Papa here.
 
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Right now I have the bias up to .9V and it appears to be running cool directly on the mosfets and around the mosfet at the heatsinks. My heatsinks are so big that the are still around 25C. I am yet to see how it sounds but last night I was surprised on how good it sound. I say this because this is one build I have sighed away from because others have said it would be too bright on horns. It was not the case with my horns.

I have plenty of mosfets indra1 so it is not a big deal if I burn up some. Just playing. Whether they last is another matter. I will keep members informed especially on the difference in sound. Supposedly they sound better the more you run them up.
 
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Right now I have the bias up to .9V and it appears to be running cool directly on the mosfets and around the mosfet at the heatsinks. My heatsinks are so big that the are still around 25C. I am yet to see how it sounds but last night I was surprised on how good it sound...........
Yet we have a body of opinion insisting that semiconductors must run HOT to perform well.
Run them as cool as you can manage and stay within the electrical parameters required for good audio performance.