Thanks again Bob for such kind words. My sticking to Zu guns, despite the plethora of "better" spkrs out there, is that in the situation of being adamant in wanting to run medium power triodes in a very large room, you are pretty much restricted to genuine high efficiency spkrs.
Horns were vaguely on my mind in 2008, but those Sjraen Ebaen articles on Zu in 6Moons around that time piqued my interest, meaning I could seriously consider 30W to fully energise a 1000 sq ft/13,000 cub ft space.
I guess had he been featuring AG Duos, I might have ended up w them.
Zus went on to be a good choice for my particular situation, and demonstrated to me, or convinced me, that the attributes of tonal density and saturation, were more critical than pin point imaging or ultra resolution. Some negatives too, my room being a bitch on harsh reflections and a devil to easily sort sub bass integration.
But something in the sound re mids density fleshing out of instruments always sounded closer to the real thing compared to SOTA spkrs I heard in the 2000s (Wilson, Rockport, Kharma, ML).
And despite a very close call on nearly going Apogee upon moving into the chapel here, I decided to stick it out w the Zus, provide them potentially with a way better acoustic, and go the extra mile on system optimisation.
And how glad I did. The Zus maintain all their winning properties of tonal density and shove, energy and room saturation even at low levels, and maybe the best spkr out there to excel on tough recordings like my beloved 60s-80s prog/fusion/electric jazz. But now have bloomed into really sophisticated transducers of the music that admittedly never convinced in my old room.
So the Zus fully optimised in a great space are suprisingly good now at timbral accuracy, transparency and soundstaging. Critically, tonal discrimination is way better, closer to what I hear in the very best spkrs like Rockport and AG, in that I can fully engage w acoustic music ie jazz and classical.
Zus still struggle w that last degree of true neutrality and subtlety that marks out the most brilliant spkrs for classical. And dynamics can never replicate what I hear from Barry's AG Duos. And it's these two latter areas that are the only fly in the ointment pushing me to investigate horns here. But I also know the very same Duos can't do what my Zus do on the majority of my sonically challenging genres.
And this is where I am. Chilled out w my system that took shape ten years ago, the core gear not swapped out for six years now, furiously modded and optimised in a brilliant sounding room in the last three years.
But w some daydreaming on the horns concept. As things stand, that concept just stays as a "what if...?" mental exercise.