Permutations in use at the moment.My opinions (are always changing).
M/DAVE > X150.8 > Utopia
Extreme power mismatch! Huge sound, dynamics, detail retrieval, and extension on both ends. Great sense of "PRaT", propulsion, and intention. Strongest sense of realism of all combinations listed here. Best synergy of all the amps I've tried with the Utopia.
M/DAVE-direct > Utopia
No weaknesses in its presentation. Very balanced tonality (almost dark!). Most nuanced leading edges. Can't match the "bigness", dynamics, and bass control of the X150.8, though.
M/DAVE > AHB2 > Susvara
Exceptionally clean, articulate, with true tones. Great sense of decay and filling out of soundstage. Precision plus musicality. Favorite synergy of all the speaker amps I've tried with the Susvara.
M/DAVE > X150.8 > Susvara
Meatier sound than with the AHB2. Less width. Probably the best imaging and depth of the combinations listed here. Was my main setup for several months.
M/DAVE > X150.8 > Freya tubes > Susvara
More depth, euphony, and musicality, with some tradeoffs in transparency. Sometimes worth it. Super-creamy.
M/DAVE-direct > D9200
End-game-worthy closed-back combination. Superior technicalities to the ZMF biocellulose offerings IMO. The Denon is fully capable of exposing the merits of the M/DAVE direct-to-headphone path. Very gratifying imaging + depth.
WM1Z > Utopia
Gives up surprisingly little to M/DAVE/Utopia (almost to my horror!). Equally smooth (yes really). Makes me wish my workplace wasn't an open office.
WM1Z > D9200
What I use at work, so what I listen to most out of all combinations listed here.
M/DAVE > [speaker amps] > SR1a
Almost over the SR1a, actually. Synergized better with the Pavane than the DAVE, TBH...
LS50W Nocturne Edition
Looks nice flanking the TV, but also better than it sounds. Maybe it's my sub-optimal room setup (non-setup). Not much of a speaker-person.