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(Remember, just because the output is taken at the cathode rather than the plate does not make the circuit necessarily function as a Cathode Follower! In this circuit, both top and bottom triodes actually function as Grounded Cathode amplifiers. If the Split Load phase splitter's output connections are swapped, then both top and bottom triodes will function as Cathode Followers. The quick test is what happens when the output of the totem-poled pair is forced positive or negative? Do the triodes now experience a great change in conduction or a small change in conduction. If the change is great, then that triode is using its transconductance aggressively to buck any change in voltage at the output; and if small, then that triode is not using its transconductance to lower the output impedance, but for gain.)
DC Feedback
Since this output stage configuration is wonderfully DC coupled, DC feedback can be applied to keep the output centered at ground potential. Without DC feedback, if the output drifts from 0 volts (the center voltage of the power supply rail voltages), the Split Load phase splitter's plate resistor will drift along with the change. On the other hand, if that drift in voltage is relayed back to the Split Load phase splitter's grid, then both the top and bottom triodes will receive countervailing adjustments voltages on their grids to counteract the drift.
An added advantage to this technique is the slightly softer warm up for the Split Load phase splitter's triode. When cold and turned off, all the circuit components are at ground potential. But when the power is first applied, the rail voltages climb almost instantly, about 1/60th of a second. The tubes are much slower to heat up and conduct, about 30 seconds. This is the time when the triode is vulnerable to damage because of cathode stripping. Normally, the cloud of electrons coming off the cathode buffers it from the high plate voltage.
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