ZMF Caldera Review and Impressions

If the tour headphone needs anything, like a new steel band or pads, or is feeling weird with adjustment, just let me knowband I'll get a label to you.

I know tour stuff and lots of different hands can out some wear on these parts. I'm happy to replace pads or put a new steel band in etc and send it along to the next person.

 

The band was still very tight when I got it a few weeks ago. Everything looked slightly used if not new. It's held up very well.

 

Thanks for the offer, @zach915m. I think we're in good shape although I'll defer to those coming after me in case they'd prefer changes.

The only thing that could be improved is tightening the screws where the rods are connected to the gimbals as I've found the rods don't stay in place as firmly as they might. It really isn't a big issue, though, and not worth sending back to the ZMF HQ, especially given that there are only half a dozen folks left on the tour. (I'd be happy to gently and carefully tighten the screws, Zach, but I won't do so without your permission).

Some glamor shots (from a poor photographer using his phone)!

















Bonus pic with Bimble Box Burl Atrium:

 

Absolutely! Vibra tite Vc3 if it needs a drop of thread locker, but a gentle tightening should be all it needs.

 

That Atrium is really pretty. The light tone of the screen makes such a nice contrast with the dark wood...you can really see how intricate and striking the screen design is.

I really admire the screens on Zach's most recent designs (Atrium & Caldera). Both are next-level designs IMO.

 

Thanks to ZMF and @ChaChaRealSmooth for making the tour possible. My chain: Apple music via iPad—UpTone ISO Regen—Eitr—DAC in Cary 306 SACD player—MJ3 (SE, low gain, no feedback, balanced output). I only listened to the Caldera with the default pads.


Frequency response. Nothing in the spectrum sounded bothering to me. Non-fatiguing, not too bright nor too dark. In the first hour, the image of piano appeared larger than life, but the headphone did not sound mid- or high-forward to me. So it achieved excellent clarity without emphases on some particular frequency bands.


Such tuning also makes the headphone suitable for multiple genres of music. I listened to large orchestra recordings as well as many songs by male and female singers. Nothing stood out to indicate that this headphone may be particular weak for some types of music.


Headstage. With the last act of Beethoven’s 9th symphony, the lead singers were well separated from each other and from the instruments spatially. Voices in the pop songs were not presented too close to my face. The headstage is quite large.


Vs. Atrium. Auditory memory, without saying, is not reliable. Anyway, I recall the loaner Atrium had more saturated tonality and more texture, and sounded more sensual, moodier. But the Caldera sound cleaner with greater clarity. Admittedly, I seem to favor dynamic headphones over other transducers in general.


Vs. stock LCD-4. I would put the Caldera and LCD-4 at the same performance level. Need more time to tell where they differ.


Vs. Sony R-10. Both the Caldera and LCD-4 were in a lower level in resolution and realism of the presentation. Once put on the R-10, I immediately heard recorded background noises which I did not notice with either planar headphone. More bass details were revealed despite lighter impact with R10.


Overall, Caldera appears to be a high-performance, workhorse-like headphone. By that, I mean the headphone can do well with many types of music in a non-fatiguing manner. In comparison, I heard some dryness with Susvara on several occasions. Also, Caldera is easier to drive and lighter than LCD-4. With MJ3, I only needed to turn the volume knob slightly more with Caldera relative to R10. But I had to turn significantly more with 200-Ohm LCD-4.

 

Great write-up!

Did you have further thoughts on the Caldera vs Susvara?

 

@wbass, I am afraid that I don't have much meaningful things to say about the contrast. I haven't got a chance to hear Susvara driven by MJ3. I auditioned Susvara multiple times at local meets. Also curious about how Susvara owners would describe differences between two headphones.

As to Susvara vs. R10, I prefer and have chosen the latter. To me, the sonic differences justify the price gap.

 

One thing that's happened lately that I didn't forsee is that a few owners wanted a brighter and more aggressive sound sig, and have ended up preferring the ultra perf pads. If interested I'll find a graph I took of the two and post it shortly.

 

First of all, thanks to everyone that made this loaner tour happen, especially @zach915m for creating the Caldera and for generally being a magnanimous headphone wizard.


Disclaimer

The usual caveats apply: These are my subjective impressions with my ears on my gear, etc.


TL;DR

The Calderas are probably the most well-rounded headphones that I’ve ever had the pleasure to listen to. I could listen to them forever without any fatigue. They are tuned neutral dark and have an even frequency response with perhaps a very slight depression in the mids. They have a lovely, natural timbre with a touch of sweetness, they are refined without being sterile, they are crisp without being strident, and they have excellent technicalities but retain musicality. The only area where they don’t excel is macrodynamic contrast. They sound a little bit restrained, but this seems to be a characteristic of thin-diaphragm orthos, generally. Overall, they are incredible headphones and I was sad when I had to box them up.


Build, Fit, and Finish

These are ZMFs. Need I say more? Build, fit, and finish are absolutely top notch, just like all ZMF headphones that I’ve owned and used.


Gear Used

Small chain: iFi Zen One Signature -> Magni x Nitsch Piety
Big chain: Yggdrasil+ OG -> ECP DSHA-3F
Wife’s chain: Bifrost 2 OG -> Bottlehead Crack

I spent most of my time listening with the Big chain, but the Calderas sounded great out of the Small chain, too. Obviously, the Small chain didn’t highlight their extensive technical ability as much as the Big chain, but they were still extremely pleasant. I even used them with the Bottlhead Crack on my Wife’s chain and they sounded good despite going against the conventional wisdom about impedance matching. In conclusion, they didn’t seem to be too picky about amps and sounded great no matter what gear I used them with.


Pads and Mesh

I mostly used the stock Lambskin pads, but I also tried the Thick pads and the Cowhide pads. The pads didn’t seem to make as much of a difference as the dynamic-driver ZMFs that my wife and I own (Atrium, Verite Closed, Auteur Classic, and Aeolus). It seemed like the Thick pads and Cowhide pads made the frequency response a touch darker, but that’s about it.

I didn’t use the Mantle Mesh because I didn’t feel like the treble needed to be suppressed. My hearing doesn’t go much above 15 kHz, though.


Sound

As I wrote above, these are exceptional all-around headphones. They are masterfully tuned and sound very natural. I couldn’t detect any annoying peaks or dips.The midrange sounds very slightly relaxed, but it’s a minor depression. The bass extends well and is presented with a tasteful, but subtle emphasis. They are not boomy headphones and they don’t have a visceral bass, but it is certainly present and enjoyable. The treble is slightly subdued, but it is sufficiently present such that the presentation isn’t stuffy or veiled. Overall, they are comfortably within the ZMF House Sound.

The staging is excellent, with a natural sense of space and great instrument separation. They could sound intimate or spacious when appropriate—a trait they share with the Atrium, presumably a result of the Atrium Damping System. Occasionally, they presented a “wall-of-sound” effect that some orthos seem to have, but it seemed to only happen on certain recordings when they got particularly busy. It didn’t seem to happen as much with very well recorded material.

The transients are clean and crisp but slightly rounded. Thankfully, the Caldera avoid sounding “plucked” like some orthos (I heard this”plucked” character with my old LCD-X). The crisp but rounded attack transitions smoothly into a natural decay, which gives notes a pleasing weight and body. There is also a slight sweetness of tone, perhaps from the reverberations from the wooden cups. As with many orthos, they sound clean and clear with good resolution and low distortion. They don’t have the slightly grainy character that dynamic headphones seem to possess.

In terms of technicalities, the Caldera are excellent. To my ears, they are on the same tier as the Utopia, but they present themselves in a completely different way than the Utopia (see below). They have excellent resolution, separation, and microdetail, but they don’t shove anything in your face. They present the music holistically, and the details are there if you listen for them.


Comparisons

Focal Utopia

As I mentioned above, I think the Caldera and Utopia are in the same tier when it comes to technicalities, but they have very different presentations. The Utopia have abundant macrodynamic contrast and are vivid, forward, and dramatic, which can be both engaging and fatiguing. In contrast, the Caldera are refined, restrained, listenable, and fatigue-free. The Utopia push all of the detail forward and make it all very obvious, while the Caldera lets you explore the sound on your own terms.

The Utopia have a smaller stage, but both have very precise imaging. The Utopia are also tuned to be mid-forward while the Caldera are slightly recessed in the mids, so vocals are more prominent on the Utopia. I’ve never heard the “metallic” timbre of the Utopia, but they have sharper transients than the Caldera and they don’t have the slightly sweet tone of Caldera. I wouldn’t call the Utopia dry either, though.

Overall, I find that peak experiences with the Utopia are higher, and they are more likely to give me the chills (in a good way), but they also have lower lows and are more fatiguing. The Utopias also seem to be more picky about amps than the Calderas, in my limited experience.


Rosson RAD-0

Of all my headphones, the RAD-0 were the closest to the Caldera in terms of overall sonic presentation. Unsurprisingly, they share many of the same ortho traits, like low distortion, excellent clarity, and good bass and treble extension. Both also avoid the “plucked” character that plagues certain orthos. The Calderas have better technicalities in most ways, digging out more microdetail and having better image separation and staging. The RAD-0 have more macrodynamic contrast and bass slam, however. The RAD-0s are also slightly thicker sounding, with more roundness and softness to the transients and more decay. Finally, the Calderas have slightly more sweetness than the RAD-0s.


ZMF Atrium

As mentioned above, both the Atrium and Caldera have somewhat similar staging, likely because both use the Atrium Damping System. They both sound either intimate or expansive depending on what the music calls for. The Atrium have much more macrodynamic contrast and bass slam than the Caldera, while the Caldera extracts more microdetail and has better resolution and separation. The Caldera have slightly better bass extension, but less bass quantity. The Atrium have the graininess associated with dynamic drivers and the Caldera has the smoothness associated with orthos.

The Atrium sounds more mid-forward, but they definitely both possess the ZMF House Sound. Both also have excellent timbre, but I think the Atrium sounds even more natural than the Caldera. Honestly, to my ears, the Atrium have the most natural timbre of any headphones I’ve ever heard. The Atrium also have a slight edginess to them in the upper mids and lower treble that the Caldera are lacking. This can be somewhat mitigated by the non-perforated mesh and/or choice of pads.

Overall, the Atrium are more “analogue” and tactile while the Caldera are more refined and laid back.


ZMF Verite Closed (VC)

These are very different headphones. In fact, most headphones are very different from the Verite Closed—I think they’re the most unique headphones I’ve ever heard, which is probably why they’re a little polarizing. The Caldera have better staging, even though the VC stage very well for a closed headphone. The Caldera are smoother and have better separation and microdetail, but the VC often present the microdetails more prominently. The VC have more macrodynamic contrast and more bass slam and more bass presence. The VC also have an interesting decay profile where the decay dips in amplitude immediately following the initial attack, but then rebounds afterwards, so they have a slightly reverberant quality to them that highlights both the decay and the attack somehow. In terms of tuning, the VC are darker and have more relaxed upper mids. They are also a little less even sounding than the Caldera.


Relative Rankings

Plankton/Microdetail

Caldera = Utopia > VC > Atrium > RAD-0


Microdynamics

Utopia > VC > Caldera > Atrium > RAD-0


Macrodynamics

Utopia = Atrium > VC > RAD-0 > Caldera


Clarity

Caldera > Utopia > RAD-0 > VC > Atrium


Transient Speed

Caldera > Utopia > VC = RAD-0 > Atrium


Decay

Atrium > VC > RAD-0 > Caldera > Utopia


Soundstage

Caldera = Atrium > VC > RAD-0 > Utopia


Conclusion

In summary, the Caldera are truly excellent headphones that provide an eminently enjoyable and laid-back listening experience. I don’t know how Zach keeps creating such wonderful headphones, but I’m glad that he does.

 

Very detailed review, thank you! One comment:

That might be amp pairing. I also own Piety and 3F. Caldera sounds too contained with them, but it's a whole different macrodynamic story with Ferrum Oor or Schiit MJ3. If I want to hear hard-hitting modern jazz, it's one of those two amps with Caldera. If I want to hear something more melody than intense rhythmic swings, it's Atrium or Verité open with 3F or DNA Stellaris.

 

I have to agree. I've never heard insufficient macrodynamic contrast (which IMO roughly translates to "insufficient dynamics") with the Caldera. Then again, I never looked for that, focused on it, etc.

I most often listen to my Caldera on powerful SS amps, my best being the Wells Milo & Violectric V281, both of which are dynamic to the max with every headphone. Now that I think of it, I may trade a bit of dynamics for even denser, more saturated tonal colors on the TC-tube amp, Icon Audio HP8; if so, the results are well worth the trade.

IMO the Caldera is one of those overachieving TOTL designs where, if you focus on one sonic attribute (ie, dynamics), all the other attributes are busy beating your brains in. That planar is kind of a thrill ride, in my experience.

 

Thanks you to Zach and the gear masters for this opportunity.

Chain: Mac/Audirvana -> Pi2AES -> Yggdrasil OG -> ACA Mini monoblocks with Khozmo attenuator.



My daily drivers are HD600 and Diana V2. Personal biases/preferences: I generally prefer a neutral sound especially in the mids. I found the HD8XX awful for its scooped out mids for example. Lately I mostly listen to Electronic and Indie and most of my live music listening is to metal. Ie, I don't have a good acoustic reference for what is "correct" in terms of sound.

The pads that were on the Caldera out of the box have a bump in the upper mids. I found myself turning up the volume all the time to get more bass and slam and that upper mid bump started giving me a headache. Went through all the pads and settled on the Caldera Deep and Caldera Suede to be the least offensive amd spent most of my time with the Suede but it was still a bit much for me.

Caldera has a wider and deeper headstage than Diana V2 although ultimate width is about the same. Diana has a narrower stage but at the extremes it's roughly the same as the Caldera. Caldera does separation a bit better and that makes it sound a tad more resolving - I'm not sure if it actually is.

Caldera does sub bass better than Diana but Diana has better midbass and it's also tighter across the bass range.

Trebble is a just a bit brighter on Caldera - but not offensive. It will come down to personal preference. I could do with either the Diana's or Caldera's trebble and be fine.

Imaging is pretty similar to me between the two.

I prefer the slam of the Diana.

EDIT:
Now that I've done my review I'm looking at the measurements. I think what I was unhappy with is the combo of a 1K dip and the peak around 4.5K. Just doesn't work for me.

 

ZMF Caldera Impressions

I’d like to thank @zach915m and SBAF staff members for kindly making this tour possible. It’s such a treat to get to audition such great gear in our own systems. This was the first time I’ve heard the Caldera, and I can see why they’ve been getting so much praise.


Preferences and caveats
I’m in my late ‘40s and can’t hear much above 14 kHz. I’m sensitive to too much emphasis in the upper-mids and lower-treble as well as fussier than most about wanting headphones to be free of congestion, veil, and a closed-in headstage. Excess warmth bothers me, and I grouse a lot about a lack of treble air. I like an open, airy, and spacious sound. I lean more towards the HD 600 than the 650 and prefer the HD 800 SDR to both. My preferred headphones are the Atrium, LCD-4 (to be modded by rhythmdevils), and the SR1a.


Setup
Mac Mini with Roon with Qobuz and FLAC/ALAC files via Unison USB -> Yggdrasil A2 balanced or balanced to Jensen PO-2XR converting to SE -> DNA Stratus.

All impressions below are from this setup but I should note that I also tried the Caldera out of my solid-state amp, the Raal Requisite HSA 1b. It was a poor pairing with Caldera, making it sound kind of dull. Worse, the sound was overly damped, perhaps more so than Dan Clark Audio headphones; the HSA 1b made the Caldera sound like a less warm, more neutral (and better) version of the Ether 2.

The Caldera sounded much better from the Stratus. I’m not sure the Stratus is the ideal pairing, though.

I compared the Caldera with my Atrium and LCD-4 but not the SR1a (too apples and orangesy).


Pad and Mesh Rolling
I’ll keep these observations brief because I didn’t spend all that much time comparing the pads. These are broad-strokes impressions of them and not particularly reliable.

Without the mantle mesh
Caldera Lambskin (stock): best balanced of the lot, with a brighter sound compared to the rest (the overall tuning remains slightly warm).

Caldera Thick Lambskin: the bass is boomier, bloomier and bigger; there may be a bigger soundstage; I found the sound a bit more fatiguing, maybe with some emphasis in the upper mids or lower treble; I only really noticed this fatigue at the end of the day, when tired, so I wouldn’t be surprised if this is inaccurate or overstated.

Caldera Cowhide: a bit brighter, perhaps, than the stock lambskins but with more of an up-front sound; vocals are more forward, and there’s less depth to the staging. A more immediate and intimate stage compared to the thick pads.

Caldera Suede: these pads soften the sound, rounding out transients, so the sound comes across as slightly more muffled and duller. These pads are good for those who like a warmer, richer, fuller, more mellow experience. They may tamp down the treble slightly.

Caldera Thin Cowhide: brighter, more intimate and with more immediate staging, more up-front, snappier, livelier, sharper, more fatiguing.


With the mantle mesh
Using the Caldera lambskin pads does tame the (lower) treble for me nicely while not making the sound all that warmer; this might be my favorite combination. The soundstage, surprisingly, sounds more spacious, if not more open.

Using the Caldera thick pads: dulls the sound a bit too much, doesn’t tame the treble as much; a bit more muffled; less open or spacious.​

Impressions
From Stratus, mantle mesh installed, Caldera lambskin pads

The tuning is slightly warm of neutral. The mids are the centerpiece of the Caldera’s presentation of music. There’s a slight emphasis in the upper mids or lower treble, which the pads can mitigate or accentuate. As such, the Caldera’s tuning can be a tiny bit fatiguing, much as it is with the Vérité, for me, at least, but thankfully the choice of pads and mesh can resolve this. Finally, the upper frequencies are rolled off slightly, and there’s not much top-end sparkle. This is most noticeable with the overtones of acoustic guitars.

The bass is outstanding. These aren’t basshead headphones. Rather, they have glorious bass when the music calls for it. As such, the bass isn’t intrusive with classical music. When the music has it, the Caldera offers bass that’s robust, rich, textured, and deep, with lots of rumble. There’s not the deepest sub-bass but it’s perfectly satisfying. The bass also has this wonderful big sound to it, both in terms of being forward and robust as well as being expansive.

The tonality is on the denser, thicker side. The Caldera may also have a slightly wet sound, although I should hasten to add that the Stratus probably explains this. With the slight warmth and the emphasis on the mids, the Caldera make for a gloriously rich, lush, and weighty listening experience.

The tonality and timbre of acoustic instruments are other standout qualities of the Caldera:

• strings are sweet, not too sharp, but don’t quite bite they sharply should; they’re smooth and have a pleasing tone
• brass: ok, a bit too smooth, not quite crackly enough; trombones and saxophones are more convincing than horns or trumpets as the latter don’t have enough bite and sound a bit too polite
• alto sax: about the best I’ve heard it, lovely and rich and slightly reedy, just as it should be
• electric guitar: again, not the most bite but great growl and texture, power chords sound great
• bass guitar: outstanding, really strong, excellent mid-bass punch, percussive, textured – a big boomy bass sound, one that’s not too loose or slow
• double bass is good, too, it conveys a good amount of the woody quality of the instrument
• cymbals are pretty good, too, not the zingiest but they’re crisp enough and well-articulated (brushstrokes on cymbals don’t turn in a smeared, rustling mess)
• male vocals are nicely presented, neither particularly forward nor recessed
• female vocals are a bit more forward and can occasionally be ever so slightly grating or sharp at times

Given the lack of bite, I also listened to the Caldera without the mesh: the treble is still rolled off but there is indeed more bite to strings, and they get some much-needed sharpness; brass instruments likewise benefit from more bite, especially the trumpet. Electric guitars could still benefit from more bite but female vocals are a bit edgier.

Transient attacks aren’t the fastest or most incisive. The Caldera doesn’t have that planar snappiness associated with Hifimen or the Abyss headphones. The Vérité are snappier, from memory. On the other hand, the decay is really very nice. As such, the transients give the Caldera more of a mellow rather than an exciting listening experience. I suspect the transients, in part, explain why people describe the Caldera as resembling electro-dynamic headphones.

The headstage is not especially wide or deep, for the most part. As with the Atrium, the size of the staging can be surprising, varying according to the track you’re listening to. I have a hunch that, besides the damping system, this has something to do with the bass, which comes across as expansive and quite airy (though less so than with the Atrium). When it comes to depth, the Caldera is quite up-front, more so than the Atrium or Vérité. Even so, Caldera’s overall staging is atmospheric and has a good amount of 3D/holography. Imaging is good; layering and separation are only ok, because of the lack of space and air.

Macrodynamic contrast is only ok. It’s not super strong, especially with classical music. Again, this could be a function of using the Stratus.

Resolution is very good and superior to other ZMFs I’ve heard. While these aren’t the most resolving headphones – compared with, say, the LCD-4 – it doesn’t really matter as the tonal richness and good microdynamics make music come across in a wonderfully engaging way.

Where the Caldera don’t quite appeal to me, sadly, is in their damped sound, which remained an issue with the Stratus and not just with the HSA 1b. The Caldera comes across as somewhat compressed, lacking in space, air, or openness. It’s also not as dynamic or hard-hitting as I’d like. And since the Caldera’s not a fast pair of headphones, the damping might combine with the slowness to make for some slight stuffiness. The Atrium has some of this damped, muffled quality, too—of course, they both use the same damping system—but the effect is less pronounced with the Atrium, in part because its headstage is more open and expansive and airy, and it has more slam.

I’ve read that the Caldera is quite picky when it comes to amp pairings; there’s a good chance I simply don’t have synergistic amps for it. For my preferences, I wonder if a more incisive, dynamic, and aggressive amp would work better. (It would be fun to try the Caldera from a Mjolnir 1 or 2, for instance).





Comparisons

Atrium
From Stratus. Caldera without mesh and with Caldera lambskin pads; Atrium, solid mesh with Universe pads

These make for nice, complementary headphones, the one showing up the limitations of the other, while both have their advantages, and each scratches separate itches.

The Atrium…

• is lighter, tonally, and not as rich or thick as the Caldera
• is brighter, with more sparkle and top-end air, providing more complexity in acoustic guitar overtones
• has longer, more lingering decay
• is more expansive in its staging, offers more space and airiness
• projects more depth to the staging, isn’t as up-front as the Caldera
• is more impactful and has more slam
  • kick drums are way more percussive
• sounds grainier than the Caldera

The Caldera…

• has a full, richer, cleaner, more precise sound
• has stronger and tighter bass, although it’s not as spacious at the Atrium’s bass
• has greater sub-bass depth
• is more resolving and provides better definition as well as clearer edges to notes whereas the Atrium can seem a bit smeared by comparison
• is more tightly controlled
• is more tactile, presents textures more clearly and richly
• has a cleaner, more precise quality to transients; guitar plucks are not as clean on the Atrium and have some fuzziness
• has more of a wall of sound effect, sometimes (and rarely, at that)
• has a more up-front presentation
  • on the other hand, it has cleaner separation and more precise imaging

LCD-4
From the Stratus, using the same cable and Audeze’s Reveal Plugin

The LCD-4…

• has a darker sound
• has a wonkier, less even or coherent tuning
• has stronger bass, with more depth
• has more slam
• has more mid-bass punch and forwardness
• is more resolving
• has a more intimate headstage
• but also more height to the staging
  • and better layering

The Caldera…

• has more even mids, and better balance through the entire frequency response range
• has better, more natural timbre
• has better upper mid and treble detail, allowing for more complexity to guitar overtones
  • cymbals also sound cleaner and more precise, zingier
• has better textures to electric guitars, including more bite
  • as well as more grit and rumble, more scream and wail
• also better delineation to notes
• bigger, bolder sound
• more open headstage
• more width to the headstage
• very occasionally, though, it has more of a wall of sound effect

Conclusion
These are outstanding headphones. They do bass incredibly well, better than almost all other headphones I’ve heard, and they’re also among the best headphones I’ve heard for lush, rich, and highly pleasing mids. Vocals sound great, and there’s a nice liquidity, as in slight wetness, to the midrange (thanks in part to the Stratus). The overall tonality is excellent, as is the timbre the Caldera imparts for acoustic instruments. The treble’s a bit too rolled off for me, lacking in top-end air, and while they could have a bit more bite, the Caldera are great for rock music, which isn’t to suggest they’re not great all-rounders; I very much enjoyed classical and jazz as well as electronic music with them.

While they’re not quite to my taste, because of the damping and treble roll off, I can see why friends have spoken so highly and fondly of theirs. Thank you again for the wonderful opportunity to hear these lovely headphones. And, wow, they’re just so very beautiful.

 

As always, thank you SBAF and @zach915m for the amazing opportunity to demo a $3500 pair of headphones at home. It’s so helpful to try things in my own setup with all the equipment I’m very familiar with.

As with all of Zach’s headphones, the Caldera is extremely beautiful and well-built. This was my first time to try the BBB strap, and it is indeed very comfortable. It’s a bit thicker and less supple than the worn-in leather suspension strap on my 5+ year old Auteur, but its extra width really distributed the weight of the headphones quite well. I had no issues with comfort.

I made the decision to stick to one amp and DAC for the duration of the demo. I used my best chain, which includes a Zen Stream > Yggdrasil A2 > Mjolnir 3 (XLR). I used my 4-pin XLR ZMF 2K Copper cable with the Caldera for the whole demo as well. The MJ3 settings I liked the most with the Caldera ended up being low gain, push pull, no feedback.

I spent most of my time with the stock Caldera pads. I briefly tried the Caldera Thick pads but felt like they took a bit of the magic away. Things sounded clearer and more precise with the stock pads. I was going to try the Suede pads but found the stock pads to sound excellent enough for my preferences that I didn’t even bother swapping pads again.

I did a lot of comparisons between the Caldera and my Meze Elite (w/ Angled Alcantara pads and ZMF Verite Silver XLR cable). The Elite has been my favorite headphone for quite a while now. It managed to win me over after many years of only using various ZMF dynamics.

Prior to this demo, I had the notion that the Caldera might be the only headphone to challenge the Elite for my top spot. As a long-time ZMF fan, I am always eager to support Zach and love the look and feel of his headphones. I also strongly value the fantastic customer service ZMF provides as well as their amazing lifetime warranty on drivers.

Now for the hard part, how did they sound. To sum it up, they were excellent from top to bottom. I didn’t find anything lacking. They weren’t too dark or too bright. When compared to the Elite, I found them more alike than different. They are both great all-rounders that manage to offer high resolution/detail retrieval while also being extremely musical/natural with excellent timbre. Every time I switched between the two headphones, I was able to quickly adjust to the slightly different presentation and immediately enjoy whatever music was playing.

Nothing stood out as being better from a technical standpoint in the head-to-head between the Elite and Caldera. They are both as technically proficient as I would ever need a headphone to be. I value musicality and emotional engagement when I sit down at the end of the day to listen to music. I also find it important that a headphone doesn’t cause fatigue when listening for a long stretch. Luckily both the Caldera and Elite allowed me to listen for as long as I wanted to with zero fatigue. The magical quality of both headphones is that they were equally adept at relaxed listening as well as focused listening. Some headphones grab your attention and don’t let you relax, and some skew too far the other direction and sound boring. The Caldera and Elite both have the perfect balance of engagement for me.

As I’ve mentioned before, the Elite is the most comfortable high-end headphone I’ve ever used. The Caldera is very comfortable as well, just like all ZMFs, but the Elite does win in the head-to-head.

If I didn’t already have the Elite, the Caldera would be at the top of my list for headphones to save up for. They exceed all the ZMF dynamics for my preferences. I still own a beautiful OG Auteur for when I want listen to something more intimate than the Elite. I personally don’t see any reason to own both the Caldera and Elite though. They are similar enough that I could be perfectly satisfied with either for the long term as my primary pair of headphones.

@zach915m You’ve got another masterpiece on your hands, well done!

 

Many thanks to @zach915m and to SBAF for making this tour happen.

I've been pretty settled in with my system and headphone stable, but the chance to hear ZMF's take on a TOTL planar was something I definitely wanted to hop on board for. I appreciate the opportunity for sure.

I kinda stayed away from digging through this thread too much because I wanted to approach this loaner with a clear mind and not have my opinions colored by everyone else's experience.

Chain is pi4/Roon -> Holo May KTE -> Icon 4 Zen -> DNA Stellaris/Moth 1-off OTL

I tried to bend this headphone to the will of the Stellaris by changing pads and driver screens but ultimately I just couldn't make it sound good on that amp. Up in the upper midrange/lower treble it was just honky, weird and distracting. I got it a little closer by adding the extra driver screen and using the thicker Caldera pads, but it was just not meant to be.

However, when I switched over to the Moth OTL things got much, much better. There were only a few times the honkiness popped up (like when listening to Graceland, for example). For the most part it was just very impressive and easy to listen to.

I didn't like the thin pads no matter the combination of equipment. They made the presentation very "wall of sound", which has been my experience with planars in the past and is the main thing that put me off of them in general. The regular Caldera pads and especially the thicker ones fix this. They open up the stage, providing depth and "making the room bigger".

The main things that I liked about the Caldera (once dialed in) were the pinpoints of sound coming from all around me, and the total lack of veil.

I get the impression that this is likely a headphone that you have to build a system around, much like the JAR800 I daily drive. I suspect that on a dialed-in system I could easily live with this as an only headphone. The change from the Stellaris to the Moth was striking, so just imagine what could be accomplished when starting from the ground up with the intention of optimizing everything for just this one headphone alone.

What made me leave the ZMF family of headphones awhile back was basically just a quirk of mine. After trying most of them, I felt like as you change gear the headphones themselves always impart their own flavor and you can't shake it. I totally understand that being cool with some folks, but it's not what I wanted. I don't think the Caldera are very guilty of that at all. I only tried them from 2 amps, but got such a different presentation when I swapped amps, that I think this headphone could likely be made to work for just about anyone, as long as you're willing to put in the work. And I say that as someone who is firmly planted in Team Dynamic Driver.

I think this is a very impressive first planar from a company known for their dynamic driver headphones, and if I were in the market for a TOTL headphone I would be thinking hard about picking up one of these and starting from scratch with my rig. As it stands though, I have my gear dialed in for the JAR800 and it works well enough for me that I'm going to leave well enough alone.

Great work Zach & his team, and a very impressive headphone!

 

I got the bright mid/treble as well and couldn't get rid of it. I wasn't smart enough to try it on the WHAMMY (for me, a dark amp).

 

Did you try the titan/mantle mesh and/or the thick caldera pads?

 

I used the thick pads and they were definitely the best. Unfortunately I ran out of time to play with the mesh after cycling through all the pads.

 

Yup. Neither for Stellaris nor for DSHA-3F (with different mismatching flaws). OTOH, very well matched with Ferrum Oor or MJ3, if in somewhat different ways: with Oor a big, modern room; with MJ3 an old-style jazz club.