Tube amps that kick ass?

I second CAT. The JL2 used will fit your price range.

While I'm partial to CAT, as others have mentioned, VTL, and Atma-Sphere are other great choices.

McIntosh Tubes are an excellent choice though more expensive than comparable amps (with better re-sale too)... especially for rock music...they are not overly revealing of flaws, excellent bass and excellent highs, they play loud ...the MC2102 is an awesome amp...2 of them will work even better.

Kronzilla with VSA VR-11s

I know this will make people's eyes roll but I will my amplifier selections to toss into the mix here are:

Jolida JD-502P

I'm really enjoying this amp with my gear. I've used 6550/KT88 type power tubes to even the Tung Sol KT-120 tubes in it and the music in my system was wonderful.

Another favorite that may not be made anymore is the Response Audio Bella Extreme 60 monoblocks. These use 2 6C33C power tubes and 5 6SN7 tubes in each monoblock.

Wonderful sounding even with a solid state preamp in the mix. The only issue I had is sourcing quality 6C33C power tubes.

I think pairing most any tube amp with the right speakers will more determine "kick ass" potential than anything inherent with any particular tube amp.

I notice a pattern with tube amps that people, even vendors, get carried away with demonstrating how little SET amp tube power is needed to drive high efficiency speakers just to make a point about low power tube amps and high efficiency speakers.

Its true a set amp can go a long way with high efficiency speakers, but I think they are only capable of being "kick ass" with the absolute highest efficiency and largest horns, 100db efficient or more. At least that is what I am hearing with various set tube amp demos to date.

The thing that tubes share with SS amps is that more tube power rather than less, though to a lesser extent,is needed to get most speakers to "kick ass" on the types of music that rely on power and dynamics to truly hit home. Pop rock and even metal, big band, large scale classical works, etc. are all good examples. Recordings of smaller mostly acoustic ensembles might get by with less, though if there is drums/percussion involved, not so much.