I would strongly suggest you consider the PS Audio BHK Sig preamp, too. You run the 300 mono's and the DSJ DAC, so you know their equipment delivers. I really like that preamp with my 300 mono's. It sure is worth a try, and a demo wouldn't be too hard to come by.
Pass Labs “House Sound” vs. McIntosh “House Sound”
I’m contemplating swapping out my McIntosh C2500 for a Pass Labs XP-20. I’ve searched the forums for posts on the Pass Labs XP-20, being that it was released quite some time ago, I didn’t find too much referencing the sound characteristics. Read plenty of reviews, but those, as we all know, are often full of audio journalistic color. Any one able to comment on the Pass Labs “house sound”, per se? Possibly what trade offs happen when migrating from McIntosh preamps.