DIY Front End 2022

Mine got shipped! Now I am gonna be that guy (I apologize): gonna be driving f4 with it using dual voltage psu. Do I absolutely need capacitors on the input of the FE? If yes what are the smallest values I can get away with, can I go smaller than 3.3? Will 2.7 work? I have those on hands. Sorry if it was beaten to death here…
 
I direct couple my Stasis FE. But I verified 100% that there is no DC from the source. Measured, not assumed.

With a cap, find one of those high pass calculators on the interwebz, like omnicalculator. Plug in the numbers for your cap value and series R. Is the result under 5 Hz? That's kinda what we shoot for. Same with the feedback loop.
 
Mine got shipped! Now I am gonna be that guy (I apologize): gonna be driving f4 with it using dual voltage psu. Do I absolutely need capacitors on the input of the FE? If yes what are the smallest values I can get away with, can I go smaller than 3.3? Will 2.7 work? I have those on hands. Sorry if it was beaten to death here…
You do not have to absolutely use capacitors on the input. I have successfully done this with an M2 OPS. You will most likely want to capacitor couple the output. You will need to pay attention to the offset from DC at the collector of the bipolar device. IIRC, Nelson discussed how to do that on the new boards. It is in this post.

Another way to tweak the offset is by adjusting the value of R7. I ended up with a value of 1k - 1k2 in my build.
 
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Can 2SK170BL's be used with the matched resistors included in the kit? Also, what voltage would work best with 2SK170BL's? I see a huge range of voltages mentioned throughout this thread and it would be helpful to learn why such a large range works with this circuit. Thanks!