I realize I may have committed blasphemy in the eyes of some here, but I decided to go with a pro amp, the QSC RMX4050a ($1499). I concluded that there are very few amps made under $1500 that can fully drive the Montis. According to ML, the Montis get down to 0.5ohm impedance at 20KHz which is lower than most other ESLs, let alone virtually all box speakers. My list got short very quickly when filtering for 1) high power 2) being able to double down on power going from 8 to 4 to 2 ohms, and 3) Class AB linear mode. Actually the QSC doesn't double down from 4 to 2 ohms, but not much else does either, so I went for the max power I could find.
Stereo Mode (both channels driven)
8Ω / FTC 20 Hz – 20 kHz / 0.1% THD 800W
8Ω / EIA 1 kHz / 0.1% THD 850W
4Ω / FTC 20 Hz – 20 kHz / 0.1% THD 1300W
4Ω / EIA 1 kHz / 0.1% THD 1400W
2Ω / FTC 20 Hz – 20 kHz / 1% THD 1600W
2Ω / EIA 1 kHz / 1% THD 2000W
So far, it's working great. No shutdowns at high frequency at high volume. The fan is a little noisy but I mostly don't notice it. I measured it at 52db from 1 foot away, and <50 (limit of my RS meter) at 3 feet. No audible noise from the amp itself, and I still benefit from the features and quality of the NAD's preamp section.
No, it's not a pretty component. I placed pictures of my kids to cover up the rack mount brackets. Those brackets are handy for moving it though - it's a 68 pound beast.
