So, why not replace these two resistors with constant current sources. FET constant current sources are readily available in two-lead packages that can withstand up to 100-volts and in small current increments up to 4.7-mA.

    This circuit should go by the name of SRSE, as it does away with all of the SRPP's push-pull functioning. Both the bottom and the top triode function in a purely single-ended fashion in this modified circuit. Both are in voltage phase, although opposite in current phase. In many ways, this circuit is closely related to the Loftin-White amplifier in that, while there is only one DC current path, there are two AC current paths.
     The bottom half of this circuit functions entirely as a grounded-cathode amplifier and the top half, as a cathode follower. And while there is no artificial increasing of the plate load for the bottom triode, the output impedance is as low as the cathode follower can provide and the PSRR figure is greatly enhanced by the top triode's acting like a high-valued voltage-dropping resistor, which, along with the added capacitor, shield the bottom triode from power supply noise.
     The disadvantage to this modification is that we must give up any pretense to constant current source loading, as the two intermediate resistors are (and can be) only resistors and not constant current sources.

     Of course, the constant current sources make the extra capacitor unnecessary, as an equal constant current can only be drawn by the bottom and top triodes in the absence of a load impedance.

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