I also have H390 and am beginning to look towards an eventual stand-mount upgrade.
I encountered many very positive reviews of the Allyssa, before reading the Stereophile review.
https://www.stereophile.com/content/alta-audio-alyssa-loudspeaker
"Unfortunately, when the Alyssas were not thrilling me, they were disappointing me with a lower midrange that lacked focus—but was it the speakers I was hearing or their interactions with the room and my amplifiers? In a larger space, with lower levels of reflected bass energies, the Alyssas would, perhaps, present themselves with a more balanced tone and sharper lower-midrange focus. Perhaps another Stereophile reviewer can audition these speakers in a larger room".
I have no idea whether this is the same thing @audiojan experienced. No other review I’ve encountered so far has mentioned this, so perhaps it is a room issue, after all.
There is a pair of Pulsars on usaudiomart:
https://www.usaudiomart.com/details/650056503-joseph-audio-pulsar-speakers/