We know by web search that the Shure Unidyne III (vintage SM57) was used by Brian Wilson on vocals for Pet Sounds - Beach Boys
This character is approached when connecting the microphone to a Pleiades (R,L) filter followed by the Pleiades V6 head amplifier.
The schematic is similar to the one below but the Nuvistor 7586 electron tube was used, Cc=22nF, different value of Pleiades bias resistor.
Later today's addition:
The heater of the 7586 is underheated by a 10Ω resistor. The input transformer is an Altec 4722. Anode voltage is approx 1.3V (1300mV). Pleiades bias resistor is 1.8MΩ. Then the Pleiadss filter can be omitted since the 1.3V at the anode provide already bass cut or high pass. So the nice Pet Sounds character sound is there just by singing 2 or more inch from the feed. The output transformer is a Pleiades 10:1 wound on Magnetec 070 ring core. Primary inductance is 77H crated by approx 672 turns.
Signal path, setup:
Male singing voice - Shure Unidyne III - Pleiades (R,L) or R=oo - Pleiades V6 head amplifier - phases inverter - Sony TC-D5 Pro - Sennehiser HD580.
When anode voltage of just 1.3V is applied no Pleiades filter is needed as there is already a bass cut due to the increased internal anode resistance driving the output transformer.
See also,the Pleiades V1 operating with an electrometer electron tube and an AAA 1.2V battery.
http://euroelectron.blogspot.com/2018/07/a-one-tube-microphone-headamp-operating.html
See also this week's euroelectron posts.
See also The Pleiades Bias - euroelectron
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