Consequently, replacing this resistor with a 20-mA constant current source would be the best solution, but probably not that useful in practice, particularly when the amplifier is driving 32-ohm headphones (32-ohms in parallel with 5k is still pretty much 32-ohms).
    A variation on this circuit is shown in the schematic below the original on the previous page. This circuit also contains a feedback loop, but the loop only encompasses the output stage and the phase splitter.   
    If we are willing to re-add the coupling capacitors or at least move the existing coupling capacitor position, then the output can be attached to the phase splitter's cathode circuit rather than its plate (the following circuit shows how). This rearrangement allows larger valued cathode and plate resistors for the phase splitter, which will lower this stage's distortion and its current path to ground can be found in the feedback resistor (8k resistor). The one problem with the original circuit lies in the high gain that results from the high ratio between feedback resistor (9.8k) and cathode resistor (100). Decreasing the feedback resistor's value does not help, as it will draw more current, which will require decreasing the cathode resistor's value as well. One step forward, one step backward.

    The solution to this problem is to use a coupling capacitor at the input, which would allow using a higher value cathode resistor on the input stage. The resulting circuit realizes a much lower closed-loop gain. And the output impedance will have to go up a tad, as the first stage's gain will also decrease as a result of the increase in the cathode's resistor value. But at the same time, the input stage's distortion will go down because of the larger cathode resistor value, which might be a nice tradeoff to make.

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