Best Integrated Tube Amp for 2.5K or Less

...don't you need some juice for these speakers?
you could try pathos hybrid amp that has 80w/ch and its new price is arround 2k.
there is mesa boogie integrated amp that can meet your power requirements. definitely you should go with higher power than nad 340.
in your situation i would go for ss plinius 8200 -- sounds like tubes very musical and worm in fact it's realy my favorite integrated amp that can smoke many separates for the price offered.

Conrad Johnson makes a nice tube integrated amplifier; the CAV-50. You could get a brand new one for $2500.

VTL It-85 is THE only amp in this price range that will be compatible with ESL or planar speakers.

If you remember Fi magazine, they reviewed a system consisting of the Audio Research CA-50 with the ML Aerius i. I own an ARC myself and have very successfully run a pair of ML Aerius with it. My room is 11 x19 x 7. I am not sure if they would have worked as well in a larger room but in my room they sounded great together. I no longer have the ML's but the ARC is driving my Vandersteen 2CE's very well.

You might consider the JoLida JD-1000A, at $1700 retail. Disclaimer - I'm a JoLida dealer. I sort of specialize in amps that work well with electrostats, since my primary loudspeaker line is Sound Lab electrostats. The JD-1000A uses the EL-34 output tube, which is more musical in the midrange than the KT88/6550 familiy of tubes, while the KT88/6550's are more powerful per tube, and generally have better bass. The JoLida's output transformer is quite good for the money, and this amp has what it takes to drive a hybrid electrostat like the Aerius i.

Among the other amps here, the Audio Research uses two 6550/KT88 output tubes, and the VTL and CJ each use four EL34 output tubes (so despite the optimistic power rating of the VTL, it's essentially the same power as the CJ or the little JoLida 302B). The JoLida JD-1000A uses EIGHT EL34's, so it's twice as powerful as the other EL34 amps mentioned here (and more than twice as powerful as the AR amp). That extra power is welcome when driving the Martin Logans, but because the JoLida does it with the EL34 tube, you don't trade off midrange performance for power. And the JoLida costs less than the others, so you can put the extra money into a tube upgrade if you'd like.

I'd be happy to answer any questions you might have.

Best of luck to you!

Duke