The Optimized Morgan Jones Earmax
In order for the WCF to optimally deliver current to the headphones the two triodes need to be operating in a balanced pushpull mode. This enables them to work in opposite phase, each drawing the same magnitude of current thus doubling the current delivery to the load. John Broskie, in a very early article from The Tube Cad Jounal, did some experiments with the WCF and determined that the best value for the plate resistor is R_{p} = 1/G_{m}, where G_{m} is the transconductance of the triode. Originally John asserted that this result is good for any value of the load resistor. After some prompting from Morgan Jones I actually calculated the value of R_{p} as a function of the load. You can read this article here. I mentioned my results to Broskie who then redid his calculations to get the correct result.
Optimizing the pushpull action of the WCF leads to the values shown in this new schematic. I made a few other changes to get better operating points for the Optimized MJ amplifier.
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The Optimized Morgan Jones Amplifier
