Introduction

ZMF made a strong debut here on TechPowerUp with the flagship Caldera open-back planar magnetic headphones. The Caldera had launched in late 2022, taking advantage of over six years of R&D and the newly developed Atrium Damping System (ADS). Incidentally, ADS—which is now patented—itself debuted earlier in 2022 with the open-back dynamic driverco-flagship Atrium. ZMF has been putting out two new headphone models each year since 2022 thus, with the Atrium Closed in early 2023 and a more affordable closed-back BOKEH in late 2023. Clearly ZMF has been working on making new closed-back headphones that not only sound good, but also occupy a different segment of the market. This meant there was room at the top to have a closed-back complement to the Caldera itself.


It is now early 2024 and, as the hypothetical schedule suggests, there is a new ZMF headphone set coming out today. Enter the Caldera Closed, a closed-back planar magnetic over-ear set of headphones which fits right into the ZMF design philosophy and boutique roots. Expect to see years of work put into this again with inspiration taken from ZMF's roots as a Fostex headphone modder and continuing to use handcrafted and assembled wooden ear cups as opposed to a more industrial design. In fact, as of the date the Caldera Closed launches, even the stock wood is quite unique in using European Ash wood that gets the Japanese Shou Sugi Ban treatment—an intentional wood charring and oil finish to make for a compelling statement. Each ear cup is one of a kind thus and the thumbnail of this review is one such example. The title image above, however, is one of the Caldera Closed LTD models releasing alongside for a small price increase and offering a different wood—Shedua/Ovangkol, an African hardwood—paired with different colored yoke rods and headband strap. If you read my Caldera review then you know that aesthetics and wood are a really big part of the ZMF headphones experience, but it is still secondary to the actual sound presentation that needs to be impressive in its own right. Thanks to ZMF for providing a demo unit of the Caldera Closed to TechPowerUp as we put it through its paces, including with a thorough analysis of multiple different ear pads and tuning meshes, in this review which begins with a look at the product specifications in the table below.

Specifications

Packaging and Accessories

The ZMF Caldera (open) I reviewed last year was a demo unit that was in use at CanJam London which, along with many, many other headphones, made the cross-ocean journey not in retail packaging. As such, I was thankful that this time I am able to show you the full retail experience that paying customers will get. Expect to see a custom Seahorse hard case—the SE 430—that has the ZMF sticker on it. This is a waterproof travel/storage case with a large handle to make it easy to take the headphones with you as needed. The case does an excellent job protecting your precious headphones with the cool twist to lock/unlock handles on the side and foam lining paired with the thick pluckable foam sheet cut out to snugly hold the headphones. The accessories are placed on the side to help prevent any scratches to the ear cups in transit.


You get to choose not only the installed pads on the Caldera Closed but also an additional set of replacement pads included with the price. There will be a drop-down menu to pick your preferences and expect to also see a guide about what the various pads will do. A thin wooden sheet with laser-engraved info works as a really nice owner's card telling you what the headphones serial number is, when these exact headphones were made, what the ear cups are made of, and also provides an assurance of the hand assembly and testing all ZMF headphones undergo. We also get a ZMF-branded microfiber cloth to help keep the headphones clean. More branding is seen on the soft cloth drawstring pouch which will contain the two cables you have chosen during the ordering process.


If you opted to purchase additional ear pads or a tuning mesh, then they will ship separately. ZMF was also kind enough to separately ship me a few different Caldera Closed ear pads and a different tuning mesh to try out and see how they change the sound presentation of these headphones. I'll have a whole page talking about these later on, but note how the pads come in bags that seem specifically made for them, including with the markings on the front for easier identification.