Best Class A amp with SLAM

Clayton M300 monos. 300wpc into 8 ohms, 600 wpc into 4 ohms, all in class A. With latest power supply upgrade, these seemingly never run out of steam. Can't say how they compare to Krell, and if slam only is your goal you should probably go back to Krell, but for the texture, naturalness and dimensionality that good class A can provide, as well as tons of power to drive a pair of Aerials, I have found these suit me well.

Dragon, when you get your MA2s run in, I would be interested in hearing how they compare with the M300s (that I also own a pair of). Do your M300s have Wilson's latest power supply upgrade?
A year or so ago, I tried to like a more "energy friendly" pair of high powered class A/B monoblocks and it was pretty much game over before it got started. The A/B amps had good bass but the Claytons ran all over them with respect to depth, texture and connectivity to the music. I have yet to hear a class A/B amp capture the body, dimensionality, and relationship between attack, sustain and decay, as well as the Claytons, or the Lamm M1.2 hybrids for that matter (that also operate fully in Class A).
The Lamm M1.2 Ref amps indeed have slam in the form of a very powerful and full sounding bass, up to their rated power, compared to some amps that start to become hard as they approach their power limit. The Lamms just lay it all out there until there is no more to give. They deliver the most powerful 100wpc I have heard, sort of like a classic big block V8 where you can just feel the power reserves without having to hear it wound up.