It would be nice to use the principles of the Pleiades V series studio microphone preamplifiers to preamplifiers for an MM (moving magnet) or a MC (moving coil) cartridge.
The preamplifier would be electron tube battery powered, at a very low anode voltage, extremely low noise and fantastic sounding.
The tubes would be the EF183 triode connected, A to G3 to G2.
A large Megohm resistor from anode to grid would cancel the self induced negative bias on grid due to space charge etc and allow operation with anode voltage less than 6V.
The tubes must be underheated for maximum information extraction.
A li-ion battery of 3.7V can therefore supply both heaters and anodes.
This will insure extremely quite operation and smooth sound.
The MM record cartridge must be terminated as usual with 47K and recommended capacitance.
Then it must be capacitively coupled to the EF183 control grid so as not to upset the condition of the free grid.
If an MC cartridge is used it can be stepped up by making a state of the art MC transformer using the Nanocrystalinne core Magnetec 073. Very few turns would be needed as the 073 has a tremendous inductance index.
The preamplifier would be electron tube battery powered, at a very low anode voltage, extremely low noise and fantastic sounding.
The tubes would be the EF183 triode connected, A to G3 to G2.
A large Megohm resistor from anode to grid would cancel the self induced negative bias on grid due to space charge etc and allow operation with anode voltage less than 6V.
The tubes must be underheated for maximum information extraction.
A li-ion battery of 3.7V can therefore supply both heaters and anodes.
This will insure extremely quite operation and smooth sound.
The MM record cartridge must be terminated as usual with 47K and recommended capacitance.
Then it must be capacitively coupled to the EF183 control grid so as not to upset the condition of the free grid.
If an MC cartridge is used it can be stepped up by making a state of the art MC transformer using the Nanocrystalinne core Magnetec 073. Very few turns would be needed as the 073 has a tremendous inductance index.
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