The idea:
To "re-purpose" V2 in that V2b (cathode follower) becomes the "added" gain stage between V1b and V2a. This is achieved via N-Mosfet source follower replacing the cathode follower.
In doing some reading, thinking and simulating (not yet tinkered), I have arrived at what I think might work...at least in simulation.
A second set of eyes would be appreciated to poke holes in the concept and design. Schematic of pre-amp to tone-stack attached (original and modified).
I think the design "visually works better" when the output from the source is either direct to source or after the first source resistor (R33) - the waveform more closely replicates the wave of a 12AX7 cathode follower. Placing it at the "traditional" resistor to ground (R13) significantly clips the negative side of the signal.
I'm for sure not certain if I'm biasing the transistor correctly. I ultimately tried to replicate downstream voltages that are produced with a cathode follower by adjusting R33 accordingly...as I'm not certain what would be the correct approach.
Thanks in advance for your insight...
To "re-purpose" V2 in that V2b (cathode follower) becomes the "added" gain stage between V1b and V2a. This is achieved via N-Mosfet source follower replacing the cathode follower.
In doing some reading, thinking and simulating (not yet tinkered), I have arrived at what I think might work...at least in simulation.
A second set of eyes would be appreciated to poke holes in the concept and design. Schematic of pre-amp to tone-stack attached (original and modified).
I think the design "visually works better" when the output from the source is either direct to source or after the first source resistor (R33) - the waveform more closely replicates the wave of a 12AX7 cathode follower. Placing it at the "traditional" resistor to ground (R13) significantly clips the negative side of the signal.
I'm for sure not certain if I'm biasing the transistor correctly. I ultimately tried to replicate downstream voltages that are produced with a cathode follower by adjusting R33 accordingly...as I'm not certain what would be the correct approach.
Thanks in advance for your insight...
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