Notice how the 3.3k resistor in the power supply serves double duty by filtering the B+ voltage for the first stage and achieving a matched plate voltage for the second stage's triodes. A safe bet would be a floating heater power supply that was referenced to about 70 volts to prevent exceeding the triode's cathode-to-heater voltage limits.
    (Of course, my brief outlining of this circuit is not the correct tube-guru procedure to promoting a new design. The generally accepted guru approach would be to write a long article for a mainstream--or is minor-stream closer to the truth?--audio magazine, such as the late Sound Practices. The article would then go on to slam all other tube phono preamp designs and go on to explain how the preamp sounds far better than a friend's supremely-expensive-tube-name-brand preamp. The article would explain how the preamp must be made with both the carbon resistors and the capacitors culled from a 1961 RCA BW television; in fact, the preamp would be named the RCA Uni-Cap preamp, or better still, the RCA-Unicorn preamp. This circuit would then live and propagate, becoming user-group and chat-room fodder; finally, someone would use a different tube and claim to have invented a whole new topology or it might mutate into a simpler circuit, as few would understand how the noise cancellation works and what is not understood is not needed; right? Oh, what a tube-audio cynic I have become.)

Fresh Topology
    If fewer caps are better, is it possible to build a multi-tube passive phono preamp with only one coupling capacitor? In the circuit below we see a constant-current-draw amplifier feeding a passive equalization network, which then feeds a common-cathode amplifier, amazingly DC-coupled all the way to the output coupling capacitor. The 100-volt DC bias voltage on the network's output allows us to use a rather large valued common-cathode resistor (5200-ohms) without having to use a negative power supply.
    The enemy of all preamplifiers is noise. Some noises are difficult if not impossible to counter, such as tube microphonics. One source of noise, however, can be reduced through an understanding and the careful applications of  noise mulling techniques. The elaborate circuitry at the common-cathode's second triode's grid (the 1-meg resistor and the two capacitors in series) is there to allow canceling of the power supply's noise from its output by introducing a small amount of power supply noise at this grid by effectively voltage dividing the power supply' noise. Thus this portion of the power supply noise can be amplified and phase inverted at the output, where it will cancel with the power supply noise at the plate resistor. A single coupling capacitor is in itself a worthy enough goal, but by adding noise cancellation, we arrive at a truly desirable phono stage.

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