I have owned Pass amps for nearly 40 years. By far the best preamp matches have been Audio Research… preferably Reference level. I also always paired with a Audio Research phono stage (and now DAC as well). I owned Pass preamps for part of the time… much preferring ARC. Just as detailed, only more musical and with better fleshed out midrange and upper bass.
Other options: Conrad Johnson and VAC. But obviously voting with my money has been for ARC. You can see my systems under my ID.