I have a good friend with Thiel 3.7's. He is using a Parasound JC5 amp with an older Pass Labs preamp and phono preamp, both are the two box versions. Not the XP20, the version before that.
I don't hear any brightness or hardness in the upper mids or highs with his system. Even when I owned fully tube based systems, I never thought he needed tubes to tame anything unpleasant in his system.
If you are considering Pass, do yourself a favor and call Kent at Pass and Mark at Reno HiFi. Both guys will help steer you in the direction you are looking to head. Mark usually has some very good deals on demo and used gear.
I don't hear any brightness or hardness in the upper mids or highs with his system. Even when I owned fully tube based systems, I never thought he needed tubes to tame anything unpleasant in his system.
If you are considering Pass, do yourself a favor and call Kent at Pass and Mark at Reno HiFi. Both guys will help steer you in the direction you are looking to head. Mark usually has some very good deals on demo and used gear.