Sound – Sources / Amplification
For this section I have used the standard, thin lamb leather pads as these are the preferred pads for my listening/tuning preference. Except for with the Mojo 2, the Atrium Closed was always connected to the balanced output. With the Caldera’s 300Ω impedance and 96dB sensitivity it on paper isn’t the hardest to drive headphone though ZMF usually recommends using a dedicated headphone amplifier. They actually sell multiple headphone amplifiers brands in their shop and they work with brands to build the best amplifiers for their headphones. Like the Caldera, the Atrium Closed is a transparent headphone, so you will hear your amplifier or source’s impact on the sound produced.
For this section we chose a multitude of solid state as well as tube amplifiers.
DAP
The Astell&Kern SP3000 without a dedicated external amplifier isn’t a source I in general would recommend for a full-sized high impedance headphone but it actually drives the Atrium Closed nicely and you can get it to very loud volumes easily. The synergy for me however isn’t really there as the SP3000 just can’t get the Atrium Closed to sound as good as it can. Don’t get me wrong, the setup sounds ok, but the Atrium without doubt sounds better when connected to a desktop amp. Here I am missing the liveliness, musicality and precision. Body wise the presentation is more neutral with more forward sounding vocals and an elevated top end presence. The lower end clarity and precision is not the very best here, though the mid layering and timbre is nice. I am being overly critical here, but the Atrium Closed simply can and does sound better.
Switching to the more powerful Cayin N8ii, with tube mode, solid state mode , Class A/AB and P+ power mode, we get a portable source with a whole different story. Here even on low gain, the Atrium Closed with the regular Power mode already sounds a lot better and balanced. It however is the Power + mode with the Class AB that really makes the Atrium Closed shine, and this both in solid state as in tube mode. You get an energetic and lively presentation, with a high level of detail, excellent PRaT and ear pleasing extension. The sound stage here has a nice width, especially for a closed-back headphone and the depth and layering is just as good. With the Cayin N*ii, the AC has good body from top to bottom, with excellent speed and energy. Bass is fast, tight and precise and it body wise is more neutral in amount. Bass reaches down low but it more quality over quantity> The lid section is spacious, natural and airy and the vocals are a little more forward and carry a higher level of energy just like the top end. IF you want a softer and smoother sounding AC with a little more bass and body presence, simply switch to the tube mode and enjoy. A highly recommended combo.
Portable
I upfront never expect the Chord Electronics Mojo 2 to work well with full-sized headphones, but sometimes in surprises in the positive way. You get the more digital, fast, precise and clean presentation from the Mojo 2, but there’s also good energy and musicality. Admittedly this combo is lighter in bass and mid-weight, and perhaps overly airy sounding but it’s also fast and energetic. It’s more like the SP3000 with an excellent technical level, but I find the synergy and musicality of the Mojo 2 better in this case. A more neutral tuning with lighter body, a lovely tight bass, energetic treble and lively vocals. Neutral, perfectly controlled and musical. It’s a good signature, but clearly not for everyone.
I have really been enjoying Woo Audio’s tube Tube-Mini with the Diana MR when I was traveling in the US a few months ago. The ZMF Atrium Closed and Tube-Mini combo gets loud fast, so be careful. Sound wise you get a little slower, fuller sound with delightful tube warmth. It’s not the fastest or tightest combo, but it’s soft, musical and easy to listen to. Weight-wise it is fuller then the Mojo 2, but it isn’t as controlled. If you prefer musicality and smoothness over speed and the ultimate detail, the Tube-Mini could be the portable amp for your Atrium Closed. I certainly like it though I would still use a full sized desktop amplifier if I had the choice or option, as the technical level and excitement just is even better.
I have really been enjoying the Shanling EC Mini cd player and DAC/AMP in my living room setup. Actually it’s more my couch setup as the EC Mini has a battery inside so you can basically use it anywhere you want. With the EC Mini, the Atrium Closed sounds a little lighter in regards to body, but it makes up for that with a higher level of energy and extension, especially in the mids, upper mids and treble section. Vocals here sound livelier and there’s just more speed and energy overall. Bass presentation here is so that quality is more important than quantity. With some of our amplifiers you really get that big thunderous bass, but here it is a more neutral tight bass presentation, though bass still reaches down low. Soundstage wise there is no particular change and the most impressive part here is the energy and liveliness, combined with the better extension. The combo is very musical and has excellent PRaT. This combo has a neutral tuning, but it is technically strong yet musical at all times.
Desktop
The amplifier I have been using most lately is the SAEQ PDA-1b and I absolutely love it but there’s something weird with the synergy here. The SAEQ is tuned especially to reproduce a live performance and this for some reason makes the Atrium Closed to sound overly airy and even hollow, it’s quite surprising. If you can look/hear past that that you get an excellent energy level, superb bass (impact, punch detail), energetic and slightly more forward vocals, and a lively top end. Body-wise the presentation is more neutral but it works well. Note that I use the -10dB attenuation setting on the front to have a little more headroom available. It’s not a bad combo at all, but the overly airy presentation for me doesn’t work for long listening sessions.
The next solid state amplifier we tested the AC with is the new Hifiman Prelude and in this setup you get a fuller sounding Atrium Closed with a higher amount of body from top to bottom. You get a warmer and somewhat slower presentation, but the sound is natural ad the presentation smooth. Bass is bigger here in body and the bass slam is impressive. Bass detail and layering is good, though bass isn’t always the tightest or fastest. The mid-section perfectly connect to the bass body wise and you get a realistic airy presentation. The 3-dimensional aspect and sound immersiveness level here is a bit lower but it makes up for that with presence and left-right stereo imaging. It’s a smoother, warmer and more romantic presentation where body, bass and softer vocals play a key role. The top-end is easy on the ears but energetic enough to deliver that engaging contrast. A recommended combo for those liking a bit of extra, bass, body and presence with a musically smooth, warmer delivery. Very enjoyable!
Switching to tube amps, the first one we’re looking at is the Auris Audio HA2-SE+ OTL tube amplifier which has a setting for 300Ohm headphones. To no surprise the synergy with the Atrium Closed is excellent. You get an airy and spacious presentation with an impressive all around you sound experience and top level stereo imaging. The Atrium Closed sounds full bodied from top to bottom, and it has that typical dynamic bass with the impactful low-end that gets you tapping your foot right away. The combo sounds musical and the delivery is slightly smooth with an easy on the ear top end. The sound stage is good, especially for a closed-back headphone, though there is still room for improvement. That said, ZMF really has tuned the Atrium closed to sound almost open-back like, and I mean that as a compliment. It’s a very musical and enjoyable combo, with a high level of naturality and especially the vocals sound super realistic, blending in perfectly with everything else. I could be perfectly happy with this combo.
The Feliks Audio Envy. At shows it’s one of the amplifiers you often see to demo ZMF headphones with, so it couldn’t be missing in this list. The Envy definitely makes the Atrium Closed sing and you on the mid-gain setting get a perfect mix of technicalities and musical bliss. Body wise this combo produces a bit more weight from to top bottom but it doesn’t add as much as the HA2-SE+, it’s more neutral here. The technical level is very high. Bass is tight, fast, punchy but also has good punch and presence. The mids are precise and revealing and have natural, airy yet energetic presentation. The vocals blend is nicely and are presented in a realistic, pleasing way. The top end is refined and energetic but has that lovely tube flavour making it a pleasure to the ear. All-in-all this combo offers an excellent sound stage in both width and depth, with excellent layering. Fun, musical, technically strong, this combo offers it all and it for ;e is one of the very best amps for the AC.
The Auris Audio Headonia with the 2A3 tube set is not available at this point as Auris is working on a new anniversary Edition of it but it is my favorite tube amp for many high end headphones. The Headonia shows less body and weight as the Envy, but it makes up for that with extension, decay and overall precision. The AC here sounds more than full enough, but you get great energy, musicality and a very high technical level. This combo is fully recommended if you want some of the tube flavour added to the AC. Timbre and layering here are a pure pleasure to the ear. I find the Atrium Closed to sound best on the 150Ohm setting.
Last but not least I want to throw in the award winning Feliks Audio Euforia EVO OTL amplifier. If you like high impedance headphones and tubes, this really is an amplifier you want to listen to. With the EVO the Atrium Closed gets a good technical level, like on the Envy, but it is lighter in weight, better in speed and more energetic. The extension and overall technical level isn’t at the level of the Envy or Headonia, but it still is excellent. You get a refined, lively and musical presentation with tube smoothness which is mostly audible on the top end. All-in-all this is an excellent combo if you like a more neutral and very balanced presentation. Bass is modest but tight, fast and detailed. It goes down low when needed but it’s quality over quantity. The ;ids are spacious, airy and have really nice extension. The vocal presentation in this combo is remarkable, while the top end is exciting but easygoing on the ears. Really nice and fully recommended.
I am sure there are dozens of amplifiers that the ZMF Atrium Closed sounds great on, so do make sure to demo first. As the Caldera is nicely transparent, your amplifier’s tuning will reflect in the AC.
Conclusion
The ZMF Atrium Closed isn’t new, but it has quickly become one of my favorite closed-back headphones. The Atrium Closed doesn’t come cheap but you definitely get good value in return.
The Atrium Closed is technically strong and musical at the same time and it’s just a pure pleasure to use all day long. For a closed-back headphone, the Atrium Closed sounds very open, spacious and realistic. It’s a headphone than can bring a smile on your face but it also pleases the audiophile with high technical requirements. A beautiful design, excellent sound and a musical experience all-in-one. That can only mean we are giving the ZMF Atrium Closed our Recommended Buy Award. It simply is another really good and beautiful headphone.
The ZMF Atrium Closed is now featured on our Recommended Buy Headphone list, where it is in very good company.
Summary
Pros:
+ Design
+ Unboxing experience
+ Sound quality (Spaciousness + Openness for a closed-back headphone + Technical performance)
+ Musical
Cons:
– Weight (for some)
– Price
