I've been working on a current-sourced and cascoded version of the Pass Balanced Line Stage. Attached is the circuit that I have been simulating. If anyone sees anything that isn't right, or has any suggestions for improvement, please let me know!

R8/R9- will be pots, as suggested by Nelson Pass. I still am not sure what to look for when adjusting this value. I was watching the voltage across the MOSFETs and the signal on the gates of the cascodes and adjusting these values for the smallest voltage drop with a clean signal on the gate. I would really appreciate someone telling me what I should be looking for.

R16/R17- standard 600 ohm load. I will be driving an A75 with this, so I think that the actual load will be a little lower (if I remember correctly, the A75 in balanced mode is a little over half that value, something like 375 ohms/input)

R20/R21- Will be 100 ohm pots.

R22/R23- Current sensing resistors for adjusting R20/R21

R5- Will be 500 Ohm pot, for adjusting gain, if for no other reason than to match channels.

R8/R9- will be pots, as suggested by Nelson Pass. I still am not sure what to look for when adjusting this value. I was watching the voltage across the MOSFETs and the signal on the gates of the cascodes and adjusting these values for the smallest voltage drop with a clean signal on the gate. I would really appreciate someone telling me what I should be looking for.

R16/R17- standard 600 ohm load. I will be driving an A75 with this, so I think that the actual load will be a little lower (if I remember correctly, the A75 in balanced mode is a little over half that value, something like 375 ohms/input)

R20/R21- Will be 100 ohm pots.

R22/R23- Current sensing resistors for adjusting R20/R21

R5- Will be 500 Ohm pot, for adjusting gain, if for no other reason than to match channels.