It is not fair for the moving coil dynamic microphones

It is not fair play when condenser, moving coil and ribbon mics are compared.


Condenser mics have an internal prepreamp. This gives them a big sound.


Dynamic and ribbon mics may sound even bigger given the chance of a prepreamp.


An easy, simple and of the highest quality implementation is the moving coil connected to a microphone input transformer. The output of the input transformer connected to the grid (through a capacitor) of an electron tube. Or to the gate of a JFET.


The circuit can be very similar to the prepreamp inside a Neumann U47 with just one underheated electron tube.


An example of a world class prepreamp is the (open source, public domain) Pleiades V6. In a circuit very similar and even simpler to the Neumann U47 an EF183 triode connected electron tube operates at only 3.7 volts from a battery. This is for both heaters and anode.


Low voltage anode operation at very low noise is achieved by a 3.9 Megohm electron accelerating resistor from anode to grid. It reduces the negative self bias on the grid induced from the surrounding electrons of the cathode electron cloud. The grid is still negative but to a much lower value.


The cathode is underheated as inside the VF14 electron tube of the U47.


The low anode voltage and temperature achieves no secondary electron emission effects. This gives possibly the quietest amplifying operation of an electron tube circuit or in fact any active device.


Ribbon, moving coil and the other microphones deserve the best.


References:


Pleiades V6 schematic - euroelectron blogspot
http://euroelectron.blogspot.gr/2017/07/pleiades-v6-schematic.html


Operating features of the Audion - Edwin H. Armstrong
http://earlyradiohistory.us/1914opr.htm


On preserving transconductance of an electron tube at anode potential as low as 3 Volts - euroelectron blogspot
http://euroelectron.blogspot.gr/2017/03/on-preserving-transconductance-of.html