OK, I have more to go on now. I’ll cut to the chase: for a combination of really top-of-the-line resolution AND punchy, dynamic bass, including some real sub-bass–it’s the Caldera going away. Throw in soundstaging that is far and above what most planars can do (historically that’s a weakness of planars, but the Caldara has the new ADS damping, and it works), and I suspect it’s the Caldera for you. It most definitely would be the next stage in detail retrieval for you.
I have to emphasize resolution again: the Caldera, like any number of other TOTL planars, really brings the detail. It’s overall slightly warm and definitely musical, but it doesn’t lop off any treble or bass to reach the sweet spot. This is the “ZMF house sound” pushed further into neutrality than usual. I did very little real listening to the Caldera post-burnin for reasons spelled out below. But my initial impression was that this ZMF might fall in the same category as the Auteur (open back dynamic) before it: a little too neutral for my tastes, whcih definitely lean in the warm, resonant/romantic direction.
But at the time I had the Caldera for review, I had a bad combination of dental pain & constant migraine that wiped out my hearing for months. I couldn’t enjoy headphones at all, couldn’t make sense of any of them, so sent the Caldera back w/o reviewing it. A related point: at the time I had them (4-5 months ago), a series of Caldera-specific earpads were not yet available for early reviewers. Thosese pads (perforated suedes; cowhides; and “thick” pads) offer the user real ways to fine-tune that high-rez planar sound. If I’d had them, I might well have used one or more of the alternate pad sets to tune the Caldera in for my preferences.
The Atrium is a whole other bag. I fell in love with that headphone. I’d never heard soundstaging like that (it was the first ZMF design to use the ADS)…not just the usual thing with where instruments are placed relative to each other, but everything about the portrayal of space itself: space around notes, space between players, all of it. The Atrium blew me away with the spatial thing which some call “hallucinatory” (kind of true). I also found it to be tonally a true “Goldilocks” design–everything perfectly in balance, top to bottom: slightly warm, as are most ZMFs, but just so well voiced tonally. It’s a golden mean sound…not as much resolution as the Caldera, but somewhat more resonance and space.
The trouble was that after awhile I fell out of love with the Atrium. It no longer was magical every time I put it on. I think what happened was I simply got accustomed used to the very different and special things it could do. Besides, I went back to listening to my Verite Open, and found it remains my favorite headphone of all. So I sold the Atrium. I borrowed it back for a couple weeks recently and was impressed by it all over again. It’s really a terrific design.
Based on what you’ve posted here, I suspect the Caldera is for you.