Another possible variation would be to use two gain stages, with the shelving half of the equalization network in between the two gain stages and the 2122-Hz RC low-pass filter following the output. This topology once again begs the irksome question of sufficient gain, as the 6DJ8-based gain stage would only realize a total phono preamp gain of +36 dB, which might be sufficient with some high-output moving magnet cartridges or with high-gain line stages. Still, this configuration  would greatly  reduce the preamp's output noise as it equalizes the signal, as whatever noise is present above 2122 Hz, no matter its cause, would also be attenuated by the final equalization network. (The output impedance of the final gain stage and the resistance of the volume control have been factored into the design of both equalization networks.)

A Different Approach
    Notice how close the inverse RIAA equalization curve is to a 50 Hz low-pass filter, excepting the flattening at 1 KHz.  (In fact, I believe that some cheap phono players back in the 60's used only a low-pass filter with a -3db point of 70 Hz or so.)
     We can rearrange the sequence of the sub-networks so that the low-pass filter is tuned to 50 Hz and the shelving network applies to frequencies between 500 Hz and 2122 Hz, but this time the shelving boosts higher frequencies  rather than attenuating them.

    Below, circuit A defines the low-pass function, while circuit B defines the shelving function.

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