try Pass preamp's with BC550!!

I've just simulated the zen preamp and balanced zen preamp both with BJT BC550 and some component value chances.. and... it show's better spec's on my spice program ... does anyone build that ... why does N.Pass use MOSFET's if the same design works better with BJT's like BC550 ? does anyone give comment's, different results ?


ooppppps did I just mix some numbers? BC549.....:) ?

[Edited by tschrama on 09-03-2001 at 05:00 PM]
Generally speaking, BJTs are more linear than FETs, it's a fact, that can be easily simulated and measured.

But this do not establish that the sound of BJTs amp is better than the sound of FETs amp. Distortions of BJTs amps can be high-order harmonics, which are very unpleasant, even if measured value is low.

Regards, P.Lacombe.
well... that may be so .. but I simulated up to the 10th harmonic at all were lower, the 2nd and third dominate, but are soem 10dB to 20dB lower than the MOSFET or N-FET versions, and the higher harmonics all were below -120dB!..

I should tell everbody that an extra input cap is nescessery in the balanced-version.. which I do not like...