I was doing some Spice analysis on my old Hafler/modified amp, looking at Ron Elliot's , and several others. I was thinking of the history of the Hafler, from the original work Erno did for Hitachi, to the DIY articles to the Hafler. Along there came the Sony integrated, which I had and remember fondly for the sound, but high noise level, and a Sanyo Plus P55 which also sounded great except for the heat pipe gurgling.
I have not found schematics for either of these. I would be curious if they share anything with E.B's designs.
I did find a hint why a driver stage in a MOSFET amp. Input capacitance of the outputs. For a low power, like the DH120, probably not needed, but if doubling or more the outputs, then it does become an issue. More outputs have advantages, but idle current goes up. I can see the attraction of current dumping so class B.
I have not found schematics for either of these. I would be curious if they share anything with E.B's designs.
I did find a hint why a driver stage in a MOSFET amp. Input capacitance of the outputs. For a low power, like the DH120, probably not needed, but if doubling or more the outputs, then it does become an issue. More outputs have advantages, but idle current goes up. I can see the attraction of current dumping so class B.