You got to be very careful. Input impedance of most Pass Lab amps is realtively low so most tube preamps will have poor match with them.
I can recommend therefore Joule-Electra LA-150 Mk2 used (but latest generation) or new or demo, call them. This preamp has two outputs: one with realtively high impedance and another with relatively low impedance so you can match it with all power amps.
I can recommend therefore Joule-Electra LA-150 Mk2 used (but latest generation) or new or demo, call them. This preamp has two outputs: one with realtively high impedance and another with relatively low impedance so you can match it with all power amps.