In sum, we can see that the long-tail phase splitter input stage does not allow as much free play as the split-load phase splitter did. Nor could we make an easy transformation into an SRPP form this style of push-pull amplifier. Nonetheless, this topology can teach us a great deal about how a push-pull amplifier works.

Common-Cathode based SRPP

     In the circuit above, we see a low gain push-pull amplifier, which may not perform any better than a simple White cathode follower as shown below. One advantage that the more complex circuit holds is that the output stage is not limited to Class-A, as Class-AB is possible in this circuit, but not in the White cathode follower (or the SRPP while we are at it).

     A circuit that looks something like a long-tail phase splitter is the common-cathode amplifier, but unlike the long tail, it offers only a single output.  It is made up of two sub-circuits: the cathode follower and a grounded-grid amplifier.

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