MPP

Fine, we have found our Nirvana WHEN they have low 1/F noise and no flicker.
I would take 100pairs too Frans if you are ok with 400 pairs.
Michael, in a minute i post the BJT buffer that sound best so far. I get absolutely stunning results after the Forsell. I have an idea how to improve the output stage and i hope that the input impedance is high and linear enough to higher frequencies. Otherwise we need Darlingtons or Sziklais at the input.
 
Here we go....
I have found out that i can substitute P1 with a fixed resistor without reference to ground
when the output has a ballast resistor. I think i took 30kOhm, the input resistor is missing,
this is where the RIIA comes in. What i would like to try is to supply the collectors of the output transistors from the emitter resistors of the current mirror. I have drawn that up and posted it here but i have not tried it.
 

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  • Buffer for Paradise Lost 1.0.pdf
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He he.. just the circuit I drew....

Here is something that can be a good foundation...Inserted the servo in the front current source

We still need a good supply for this...
 

Attachments

  • Paradise lost.JPG
    Paradise lost.JPG
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I see mirrors... mirrors everywhere ! :D This could freak out some potential builders, but actually signal path is not so complex. I like it. Had a look to my bc337 bag, they are phillips made from who knows what age. I hope they didn't switched to new process. Anyway, it's good general purpose bjt, I use it everywhere, so no need to throw them out if noise is not up to expectation.