M.S Electrical Engineering, University of Southern California (2017)Here is more of the text George didn't include which precedes the above text by Jacob VonWagoner:
Pros for BJT:
BJT’s are capable of handling higher output currents for signal outputs and can have lower output impedance in amplifiers intended to drive a low input impedance load or deliver significant amounts of power, this is a huge advantage.
Cons for MOSFET:
Can’t drive a low-impedance load very well.
BJT's can give you a lot higher gain. Just take a bunch of components and compare them, and you'll find the BJT's give you better gain characteristics and therefore require fewer gain stages.The words 'gain', 'linearity' and 'bias voltage' tell you that this has nothing to do with class D amplifiers which do not operate their output devices in the linear region. Instead class D amps go from Off to On and spend as little time in the middle (linear region) as possible. This is the reason they are so efficient.
BJT amplifier stages are much more linear than MOSFET amplifier stages, as the gain doesn't depend on the bias voltage. This gives better fidelity.
Obviously while all this stuff is correct with regards to conventional amplifiers it has nothing to do whatsoever with class D amps. George's remonstrations notwithstanding.