In this case we are simply looking at a complementary pair of
followers. Perhaps one of our regulars would like to jump in
with a circuit. For 1 amp bias, it takes about -7 volts or so
from base to base for bias and there are no Source resistors,
only nominal Gate resistors like 100 ohms to preclude parasitic
oscillation.
Last week I was doing some patent searching on tube-ish FET preamps. I found this one from 1977 interesting
Signal amplifier circuit with a field effect transistor having current... - US 4008442 - IP.com
In the background, the author states "Recently, field effect transistors having current unsaturated characteristics like those of a triode vacuum tube ... has attracted attention as an active semiconductor amplifiying element for an audio signal amplifier circuit." He references a Japanese patent of 1973 for the invention of these special FETs.
Like all patent apps, it goes on to make general claims for the invention, showing a number of circuit configurations with no component values given, only equations.
But anyway, perhaps the author was using the V-Fets mentioned here, I thought it might be relevant. I certainly am intrigued by one of his circuit configurations, doesn't look too different from a conventional preamp, I may try to scrounge up a few parts and build it.
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