So when the driver tube sees an input swing of +62/-62 volts, its plate will swing -221/+195 volts, which in turn this imbalance will counter the imbalance that the output tubes will force onto the its output voltage swing, as it is the inverse of the output stage's imbalance.
      The unfortunate feature of this amplifier is that because the 300B mu is low, the output stage never realizes it full potential output, as the cathode follower output stage's low gain requires a much greater voltage swing at its grid to bring out the full output power that the 300B can give. Thus a better choice for an output tube might be triode connected 8417 or EL34. In the schematic below, we see an EL34-based output stage. This amplifier would provide about 15W of relatively inexpensive, clean, pure single-ended power. 
      The power amplifier's input stage also uses complementary inverse pre-distortion to lower this stage's contribution to the amplifier's final distortion figure by not adding excessive distortion to the mix. Thus the same principle of inverse-complementary-distortion cancellation that lowers the output stage's distortion is used to in the input stage. The same triode, the same cathode-to-plate voltage, the same load resistor value--all are used to inverse symmetrically cancel the distortion from the input stage.

    The end result of all these techniques is an amplifier with a low output impedance and low distortion and wide bandwidth, an amplifier that does not use feedback (at least not a global feedback loop). The cathode follower output stage deserves some comments. This circuit employs 100% cathode degeneration of the output signal to keep the output in inline with its input. If the cathode fails to move as positive as the grid moves, then the grid effectively becomes more positive and the tube's conduction increases, which will force the cathode to a greater positive voltage. Conversely, if the cathode falls less negatively as the grid falls, then the grid effectively becomes more negative and the tube's conduction decreases, which results in the cathode's voltage to collapse. In other words,  the cathode follower output stage uses all of the output tube's transconductance to force the output to follow the input signal. This short, quick feedback mechanism also brings the output impedance down and extends the bandwidth. It also serves to lower the transformer's distortion contribution, as output transformers distort least with low impedance input sources. This is an import advantage of this output stage, as the transformer is not enclosed in a distortion lowering feedback loop.

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