Originally Posted by justanoldmuso
its a pity one doesnt see more jfet
audio schematics while op amps one sees lots.
Bipolar transistors are still a little quieter than JFETs, though the best of each are quite close to the limits of physics at room temperature.
Bipolar transistors can be a little lower distortion than JFETs, though in the mic pre-amp circuits that's not all that significant. In truth distortion in microphone itself probably dominates.
OpAmps can be surprisingly good and are probably easier to manage. For many purposes there's really very little benefit in using discrete parts. 1dB maybe.

Bipolar transistors are best for ribbon mics with no transformer as they can be better matched to the very low impoedance, but tring to do that on phantom feed is probably a lost cause and again we're likely talking only a dB or few.

Cooling the circuit substantially can improve all these things be several dB, but again that's not something one could really do electrically/electronically via phantom power. It might be feasible to chill just the junction of transistors with a tiny Peltier device, but the power management would be crazy, assuming it's even technically possible.

Jazz relative beginner, starting at a much older age than was helpful.
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