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If a push-pull version were made, it would have be run in strict Class-A mode to ensure that the inverse distortion cancellation took hold. Note the common, un-bypassed cathode resistor that works to mimic the output tube cross-coupling in the output transformer. (Actually, this circuit would probably work best with an interstage coupling transformer.)
Realizing Full Output
The problem we face is that in order to realize the full potential power output of either single-ended or the push-pull topology, the output stage requires a drive signal in excess of the drive signal available from the driver stage. One way out of this problem is to use a slightly higher value for the driver stage plate-load resistor, which would increase the potential power output at the expense of a slightly higher output distortion. How much larger should this resistor be? The math is simple enough:
Ra' = Ra + Rk
In the example just given, the plate resistor would be increased to 5741 ohms. What this value does is add the absolute value of the bias voltage to the peak output voltage swing of the driver stage, which compensates for the voltage gain lost by the output stage.
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