Looking for great Amp for Martin Logan Prodigy woofers

I am rebuilding my audio system; centered around getting the most out of the Martin Logan Prodigy.  I have Audio Research VT 100 (intended to drive the panel section).  Now I am looking for a second amp (stereo or Mono blocks) to drive the low end.  I've seen a lot of people using McIntosh, but I am not going that way.  I want a used, well-built and rugged, yet musical amp, (like the Krell FPB 300).  The budget is $2.5k  Does anyone think Krell is the way to go? Suggestions please.
Thank you
theaudioman; Sorry, I missed the part where you gave your budget in your opening post, which would rule out the M-1’s

Overall, I would say that you’re better off with one or a pair of better mono amps vs trying to run one amp on the highs and something different for the lows. I would try to do two of the same amps, which in this case would be adding another VT100. 

A better sounding amp is just that - better! The VT100 will run your Prodigy’s fine and I don't know if putting a Krell on the bottom will really give you all you're looking for. Something you could consider is upgrading your speaker cable and having them made in a bi-wire configuration, unless you like to change and go through cables, then it’s usually easier to sell non bi-wire versions.  Just my opinions...


They xover at 250hz, so just a Class-D for the bass will be fine that’s what their good at fast dry bass should match up to the speed of the esl's better.
Also get one with input level controls and that has higher gain than your esl amp, as you’ll have to match up the gains.

And it’s also good to have level controls on the bass amp because on hot humid days the esl panel looses a couple of db efficiency, and the sound "can" get a touch bass heavy, but with the level controls you just back off the bass a touch on those days

Cheers George
Two VT100s would generate a lot of heat. Not saying it's a bad idea, I've had one and replaced it with a Ref 110. People do bigger tube amps all the time but that's like 7 or 8 amps of standing current and 16 6550s in one room.

That's dedication.