By a good margin, the most transparent and open sounding amp I’ve had in my system was the Liberty B2B-100 made by Peter Noerbeck of PBN (my amp is a McCormack DNA 0.5 Rev. A). Liberty is his direct-to-consumer brand that benefits greatly from trickle down technology from his lauded Olympia amps yet are at a much more accesible price. This amp threw the most holographic and airy soundstage I’ve ever heard, which was likely aided by what seemed like a complete absence of background noise -- everything just appeared to be floating freely in completely clear, thin air. One of the really nice features of this amp is that it can be run in low- or high-bias mode. It sounds great in low bias but even better and more fluid in high bias, and although it runs a little hotter in that mode it’s still not hot like a pure Class-A amp. I left it in low bias when not listening and flipped the switch for critical listening so the amp was always warmed up and ready to play. Peter told me the amp sounds significantly better in mono-block form, which is saying something because this amp in stereo was quite special, and even in mono configuration the amps would only cost $6k for the pair. I’d bet Peter would grant you some form of a trial period if you asked, and given what you’re looking for I’d be shocked if you ended up sending them back. His amps are a well-kept secret in this hobby, unfortunately. Best of luck in whatever you end up getting.