which tube mono blocks?

I suspect none of you who have responded so far have heard the Coincident 211 Dragon monoamps - 80w/channel . They are superb and are a must audition .

While I am partial to NAT Audio since my firm also imports the line, I would like to suggest doing some research on this incredible line and more specifically on the model called "Generators" that can run any loudspeaker from 2ohm up to 16ohm and is 180wpc into 8ohm and 240wpc into 4ohm. They are within the price range of what you're looking to spend.
www.nataudio.com and www.musicalsounds.us

Good luck

If I'mn not mistaken, Wolcott ads say they are designed to be run with demanding loads, in particular flat speakers. they should fall into your budget as a stereo amp. Monos might not though.

check 'em out, they're very well regarded and a long standing company. Whenever I see them posted here they sure don't stick around long.

Darkmoebius, just for the record, I stated that about **all** amplifiers, tube *or* transistor!

To restate: If your goal is sound quality, your investment in your amplifier will be best served by a higher impedance speaker (8 or preferably 16 ohm), all other things being equal. If your goal is sound pressure and you have a transistor amplifier, that goal will be better served by a lower impedance speaker such as 4 ohms.

All tube amplifiers are challenged by 4 ohm loads regardless of the technology of the tube amplifier. In the case of a transformer coupled amplifier, you often loose an octave of low frequency bandwidth going to the four ohm tap, and distortion increases, usually along with a slight loss in power.

People often talk about the ability of a transistor amplifier to double power, but if you already have found tubes to be preferable, then you also know that that ability has nothing to do with good sound, so long as you choose the right speaker. There really are two paradigms that tubes and transistors loosely fall into, and if you mix equipment from the different camps, you will get poor performance. See

http://www.atma-sphere.com/papers/paradigm_paper2.html

for more information.