Tube Amplifier for Thiel

I have used Thiel speakers for many years, in many different systems. They need power, but much more importantly, the need solid state or high powered tube amplifiers that can provide substantial amounts of CURRENT into low impedance loads.
Three good choices that are generally in your budget are the MCCormack DNA amplifiers (like the DNA one), Classe amps from a few years ago, and the previously stated Conrad Johnson solid state amps like the MF 2500.
There are a number of others as well.
I'd use a warm sounding tube preamp that has good impedance match with the amp. Select the Amp first, then the preamp. The Theil 3.6 is capable of beautiful music if fed properly.

Try BEL 1001 monos, in your price range, tubelike w/bass,been have used them to drive Thiels, Apogees, Maggies, and currently Wilsons. Saw a pr. on Canuck Audio.

I owned the 3.6 many years ago. They need "current". I tried Krell KSA 100, Classe CA-150, and VTL 225 monoblocks with the 3.6. They were fine. However VTL 225 could not control the bass as good as the other two SS amps. A good case in point is when I recently auditioned a 180 wpc high quality tube mono amps with the Revel Salon 2, the bass was not there. It is the current that counts.

When I got the Brown Electronic Lab (BEL) MKIII monoblocks, the sound of the 3.6 became spectacular. I used tube pre to introduce some tube characters into the sound though. I was using CAT SL-1 Signature. Unfortunately, BEL is not around anymore. You can only buy used and they are very rare.

I recommend good SS amps (at least 100wpc but 200wpc or more is better) that can dive deep to 2 ohm with the 3.6 and also a good tube preamp. If you really want to use tube amp, I suggest you try it home to make sure it can work with the Thiel. For SS amp, I think the Parasound JC-1 monos could be a good candidate.

Buy the first pair of used Bob Carver VTA180s you see. Retail prices vary.

They run cool, hand made point to point in the U.S. have a 2 ohm tap and a seven year transferable warrantee.

They drive my Avalon Eidolons effortlessly.

Ahhh. Played my 3.6s at volume today.

Clean, loud, lithe, liquid, beautiful music. (Like a beautiful gymnast.) And lush, too.

Gobs of power from my Carver. Made me feel refreshed from listening, but also just knowing that there's acres of headroom was boffo all by itself.

No strain whatsoever.

The M500t is rated at 370w/ch and 470w/ch dynamic for 8 ohms and 4 ohms respectively. (If you choose to have Rich Pecoro do his Mark 2 upgrade, these numbers become 520 and 920, with 1214 at 2 ohms, where the 3.6s live. --Not affil., just sayin'.)

The M500t was voiced to sound tube-like and has been described as the most musical of Carver's M amps and one of Bob's favorites.