Advice for speakers under $4K for mixed use

A used pair of Thiel CS2.4 ($5000 retail, $2000-$3000 used).

"The Thiel CS2.4 is a great loudspeaker, one of the very best I've heard regardless of price. Its treble soars and its bass plummets, but all the while the CS2.4 sounds utterly neutral and musically communicative. This speaker looks gorgeous and has the earmarks of heirloom-quality craftsmanship."

Soundstage!

PSB Synchrony One $4500 retail:

"Furthermore, the bass wasn't just deep, but well controlled, super tight, and without any boost or emphasis in the upper-bass region (100-150Hz or so) that gives the illusion of really deep bass when it's not there. The One delivers the real thing -- nothing I heard in my room would cause me to dispute the 30Hz specification."

""However, something I didn’t expect from the Synchrony One impressed me far more: the level of midrange clarity, detail, and tonal accuracy."
Soundstage!

I really like the Thiel sound (or lack of sound) but there are a lot of good choices in the $4000 price rang that I am sure other people will chime in on. It is best to get out and demo speakers.

I also own a pair of 2.4s and while they do need a solid amplifier (no pun intended lol) to sound their best you can get away with much less. I have tried 3 amps on the CS2.4 at this point. Mcintosh 252 (250 watts/ch class AB), Wyred 4 Sound ST500 (250 watts/ch class-d), and Rotel RB-1072 (100 watts/ch class-d and part of my second rig in the bedroom).

I liked the Wyred for sound the best over the Mcintosh 252. It gave up nothing to the Mcintosh 252 and added bass control (slam/punch). But I pulled out the Rotel just for kicks and it too does a pretty good job. It is not as refined in the top end or mids as the ST-500 but it does pretty good at only 100 watts and much better than you would thing for the $500 I spent on it...

As the people above have commented room size and seating distance are very important as to how much power you will need. Things like hardwood floor vs carpet make a big difference too. But most of all it comes down to how loud you listen. Remember that it takes twice the power for a 3db increase in sound. So if 20 watts gets you to your listening level a 100 watt amp will give you about 6db of overhead. There are a lot of factors but the doubling of power for 3db gain is a good place to start from.

I listen right around 75-80db and on the Mcintosh 252 (it has a rough gauge) I was using 12 watts with 20 watt peaks. Of course this will very with preamp gain, room, etc.

Now there is a theory that more power adds speed and control and there is some truth to this idea IMO. But there is a point where watts to not mean much and quality quickly takes over. Other things to consider are damping factors of the amp for bass control. Speaker impedance balance also matters. Anyway sorry to run on and on. I am sure you already know most of this stuff.

PS. I personally would alway buy the speakers I like first and work the amps and front end around them. Speakers will most likely be the weak link.