Class A Solid State Sound

How about PS Audio's BHK  Signature 300 with a tubed input stage and MOSFET output stage using exclusively n-channel devices for both the positive and negative signals.  Claimed power output is 300/600/1000 wpc into 8/4/2 ohms and according to JA's measurements those specs are mostly confirmed with 370/620/950W into 8/4/2 ohms, although like many manufacturers, it appears they sort of fudge the 8 ohm power rating (lower than actual) so they can claim that the amp " doubles the output current with half the impedance."

I appreciate that they provide a power rating at 2 ohms but cannot help wondering the reasons for JA's comment that the amp "was less comfortable at lower powers into this low an impedance" (i.e., a 2 ohm load), and Fremer's comment that, "there's still more weight, power, and physicality to be had in the very lowest octaves."  Curious why an amplifier that provides 950 wpc into 2 ohms would be anything less than a powerhouse into low octaves.  Does the MOSFET output stage have something to do with it or, how about the dual differential design?

output stage using exclusively n-channel devices for both the positive and negative signals

This topology may not have low enough output impedance vs. push-pull complementary N/P pair.  And output impedance is freq. dependent so may be that could explain its performance at 2ohm.

JA - "The output impedance (including the series resistance of 10' of speaker cable) was on the high side for a solid-state amplifier, at 0.16 ohm at all audio frequencies."

Topology is by far the greatest determining factor in how a transistor delivers current to a load.

Given similar topologies it’s the final stage, "the output stage" that will determine how much current will flow into low impedance loads.
Complimentary class-A/B devices of the same pair numbers, the BJT will deliver far more current into low impedance loads than a Mosfet can.
Again end of story, your making yourself look ****** by saying anything else.