Anyone who's been interested in the audiophile headphones hobby will likely have heard of ZMF. Beginning, as a few other smaller brands have, with modded Fostex T50RP headphones and then making their headphones, ZMF went from a one-man operation to a team that never seems to have forgotten its roots despite it being very easy to be put up on a pedestal by the audio community. If you've had the chance to meet ZMF at an audio show, you will leave knowing their names and their personalities too. For example, Zach is this passionate guy who enjoys discussing different wood types and woodwork while trying to use the word "chatoyance" in a conversation as much as possible (I kid). They go around pulling pranks and participating in them while also reminding you they are just as much audiophiles interested in what others are up to as much as improving their own offerings. There's no pressure to buy anything or leave their booth/room and they even make sure you leave with more information to make a purchase even if that means going with another brand's product. In an industry where the profit margin is key, this is refreshing to see. If you wanted an example of what I mean, just look at this thread posted by someone who recently lost their father and worked with ZMF to make two custom headphones using a piece of wood that was important to the deceased family member. I'll admit to have become emotional reading this and that's also a great segue to what the Caldera is all about.

If you go read the dozens of reviews available online—many of which are from everyday members of the community who had loaner units from ZMF, another move that is rarely seen—the common theme seems to be how the Caldera manages to eke out a unique sound signature unlike most planar magnetic headphones on the market. It does so while also being engaging and lively, getting people to appreciate music they have and reminding them these headphones were made for that rather than purchasing music to justify buying headphones instead. An analogy in the PC DIY world would be how many people get the high from planning and building their own PC but then not actually enjoying the games that the PC can run with ease, instead looking for an excuse to build a new PC or upgrade the existing one because a newer game might benefit from it. I've admittedly also been caught in the detail retrieval-cost game wherein I expect to see more expensive headphones be all about resolution first and having a flat frequency response from the bass to the mids alike. The IEM world is a good example of what would happen if everything was tuned the same wherein things are becoming repetitive and it's hard to get excited about something. Thankfully the headphone space is still allowing room to try different things at various price points.

The Caldera isn't for everyone. It has a warmer tonality that doesn't come off as the cleanest sound in the world, and it isn't the most resolving set either—probably a good thing here given the non-fatiguing frequency response. It's also damped so you might expect to get softer bass and mids and yet it's the other way round. There are several pieces of tech which went into the Caldera, some of which are patent-pending too, and the end result is a set of headphones which walks a fine line between sounding like a dynamic driver at times—impact, timbre, transients—while retaining planar separation and layering. I also thought of AMT headphones in terms of the increased weight to the tones, especially in the mids, as a result of the focused airflow going to the ears. This was made possible by going for a more aggressive mid-forward presentation thanks to the "CAMS" system with the asymmetric magnets, which could have gone badly and resulted in overly elevated treble peaks were it not for the innovative atrium damping system. It results in a set that doesn't sound like any other I've tried and I suspect it won't be long before people try to put out headphones that will have reviews talking about how it reminds them of the ZMF Caldera. Whether or not you like the sound, do go spend some time with ZMF if given the opportunity and see the various designs on offer. Chances are high something will catch your eye, just like the Caldera did for me. I'll happily recommend it to people thus and also award it a deserving innovation award for the novel back-damping system too.