Other topological variations are certainly possible. An input amplifier with no equalization could feed an inverting plate-follower amplifier with all of the equalization, which would accurately follow the RIAA beyond unity gain.

     An inverting plate-follower amplifier with only the 2122 Hz part of the equalization might make a good first stage of a two stage MC phono preamp, as moving coils cartridges work well with low impedance shunting impedances, which this first stage could easily present. The second stage would actively finish implementing the 50 to 500 Hz part of the equalization curve.
    One complaint might be that any inverting plate-follower amplifier will invert the phase at its output, which if it does cascade into another inverting stage, will result in phase inversion at the output. This is a non-issue, as the leads to the phono cartridge only need to be reversed in phasing to set the output straight. The cartridge does not know how it is being hooked up to a preamp; its coils do not "know" what phase configuration is "correct."
    In fact, there is one distinct advantage to having the preamp invert the phase at its output: it lessens the chance of the output signal re-circulating back into the input and causing oscillation. The danger any high gain non-inverting amplifier faces is that its output signal is so much greater than its input signal that only a small fraction of its output being fed back to its positive input can lead to wild oscillation. On the other hand, an inverting amplifier cannot oscillate under the same conditions


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