Preamp recommedations for Pass Labs XA-100.5

I think Pass makes great amps but I never liked their preamps. I would look at Ayre, BAT and Aesthetix.

When I got an XA30.5 I ran my source direct to the amp (it has a volume control) to bypass the highly regarded preamp I was using and I was blown away by the clarity and resolution that I was hearing. This experiment led me to look for a preamp that was as transparent as possible. My search brought me to Placette. If you are looking for a preamp that doesn't color the sound, then I would check it out. I got the active version because I understand it sounds a little better than the passive version. There is no gain in either versions, so your source would need to be adequate for this to work.

I took my Pass XA160.5 over to a friend's house to compare the Pass XP-30 to the Ayre KX-R(?). They both sounded excellent, but if I were to buy one, I would choose the Pass pre. It was slightly smoother with less emphasis on the high frequencies. They seemed equally detailed, but the Ayre seemed slightly tipped up. I would describe the Pass as neutral or slightly warm, where the Ayre was definitely on the cooler side. The Pass seemed just slightly better balanced to me, though I'm sure others would hear it the other way around.

I own the XP-20 which is also excellent, just not quite as refined, smooth and detailed as the XP-30.