The Aeolus ZMF model was the highlight of the company’s lineup in 2018. It’s an open-back, full-size pair of headphones, a variant of the closed-back Atticus.
Technical Specification
Type: Open-back, over-ear Drivers: 50mm dynamic TPE (Thermoplastic Elastomer) Impedance: 300 Ohms Sensitivity: 98 dB/mW Cable : Detachable, mini-XLR connectors Retail price: from USD$1199 to USD$1499 (limited wood) + ear pads/cables upgrades
Build and Style
Packaging
ZMF provides a protective case as the packaging box for their headphones. These are Pelican style cases, following the design of other luxury headphone brands like Audeze or Meze. They are very rugged and would be the perfect case for outdoor use, but lack portability. Inside the case, we find a ZMF logo sticker and an owner’s card, with the manufacturing date and serial number. Buying the brand new Aeolus (or any other model from ZMF) guarantees you a lifetime warranty for the drivers, but if resold, the warranty is voided. The Aeolus comes with a stock 6 foot long ¼ inch cable, but upgrades are also available, from OFC (USD$60) to 2K Copper (USD$350) and more. The Suede ear pads visible on the picture above are an option as well (USD$60).
Finish
The stock wood used on the Aeolus is sapele. ZMF has many other wood options as well. The current Aeolus Limited Edition is made with blackwood cups. The headband is made of cowhide leather, and has one of the best feels out of all of the pairs I’ve ever used. The metal gimbals seem to be really sturdy and have no play. ZMF offers a USD$250 magnesium chassis option for their limited models, reducing weight. The wooden ear cups combined with the drivers grills are eye-catching. The sapele grain is gorgeous and makes every headphone unique. Overall, these are one of the few headphones I genuinely find stunning.
Comfort
Ear Pads
All ZMF ear pads are very comfortable and this model is no exception. The aeolus has good ventilation and uses soft leather. The ear cavity is 56x71mm and moderately deep, so most people shouldn’t have trouble fitting.
Headband
All ZMF headphones are designed with a suspension headband – one metal piece is holding the structure at the cups, while one strap is resting on the head. This is an ideal design for most people, as it prevents hotspots and discomfort.
Weight Distribution
The Aeolus, in its sapele wood variant, weighs 473 grams. Not amongst the heaviest headphones out there, (LCD-X, LCD-4, Kennerton Odin) but definitely above average. With its large plush pads, good grip, and the suspension headband, the Aeolus’ weight shouldn’t be problematic. It has top notch weight distribution, and bending the metal headband to size will add to comfort as well.
Sound
The Aeolus is a great example of how ZMF headphones sound: warm, classy, and relaxing. Despite the high impedance, they don’t take much power; any entry-level amplifier can drive them.
Lows
There is no doubt that the Aeolus is a bassy pair of headphones. The low-end is probably the first thing I noticed. The mid-bass is greatly emphasized and adds a lot of depth to the sound. The sub-bass extension is also quite solid, considering it’s a dynamic driver in an open-back design. Pleasant rumble can be heard without any problems, although you don’t get the absolute perfect extension of planar headphones, generally between 20 Hz and 40 Hz. Even though I am usually a fan of a raised sub-bass response, I highly appreciate the mid-bass boost of the Aeolus. It may be a bit too much for some bass-heavy genres such as hip-hop or EDM, but there’s a lot of enjoyment to benefit from. I sometimes find the bass sounding slightly damped – not as controlled as I prefer.
Mids
The midrange is pleasing and smooth. The lower-midrange is raised around 150-400 Hz and gives body to both the voices and instruments. Like the mid-bass, the lower-mids can be occasionally a tad too elevated for my taste, but certainly pleasant for people who enjoy the balance of warmer headphones like the HD6XX or TR-X00. The upper-midrange is a critical area of the frequency response. Being too elevated will result in an unpleasant sharp sound, sometimes even creating a “telephone” effect. Being too recessed will compromise the presence region and possibly impact an instrument’s timbre. The Aeolus are mildly dipped around 1-4 Hz and will greatly work with brighter musical genres like pop. Rock and metal also sound awesome, and generally, audiophiles enjoying these genres prefer a slightly dipped presence region for a smoother tone.
Highs
The highs of the Aeolus are a tad recessed, but have enough energy around 6-7 kHz. I tend to prefer sparkly treble presentations with a good amount of air past 10 kHz and no harshness between 5 and 10 kHz. The Aeolus, while not being harsh, fails to deliver the treble extension and airiness I’m expecting from a high-end pair of headphones. It has some air, but is not an improvement over a midrange model like the HD6XX. Hopefully, it does not sound dead like the Kennerton Vali I had recently and should be great for most folks. Treble is certainly the hardest part of the frequency response to reproduce with accuracy in headphones. We often find major dips or peaks there and most products sound unnatural, grainy or harsh in that region. The Aeolus is a smooth sounding pair of headphones, but I wish the treble was a bit more detailed.
Staging
To me, the Aeolus has a roomy presentation, easily wider sounding than the HD6XX, even more so than the Focal Elex, Hifiman HE-6 and possibly the Audeze LCD-2. (I do not have a LCD-2 at home so I’m not able to do a direct comparison between both headphones.) The imaging is pretty good. No inaccurate presentation with instruments in the center and both sides. Every aspect of the staging is filled when needed. We are far from the inaccurate imaging I have heard with older headphones like the AKG K701 (it lacked center image) or Audio-Technica ATH-AD900X (the sound seemed to come from “behind” the ears).
Technicalities
I always favor tonal balance and timbre over technicalities, but I am expecting them to be solid regardless, especially past a certain price point. High-end headphones should produce a punchy sound, with great sense of dynamics. The transient response would be fast and precise, with solid resolution and finesse. The Aeolus is fairly resolving and quite dynamic. However, at USD$1200, it’s not the most resolving model I have heard. The detailing of the Aeolus isn’t better than the Focal Elex, which is USD$500 cheaper. Some discontinued headphones that sit in the sub-USD$1000 range, such as the Sennheiser HD800 or Hifiman HE-6, offer more resolution. Regardless, the Aeolus has great slam and dynamic range, and you won’t find much better for the price. The speed is acceptable, but the wooden cups cause there to be a reverb effect. It creates an “echo” feeling that is part of the ZMF signature sound. I like it, although it’s a bit over-emphasized and can damage the decay speed.
Alternative pads: ZMF Universe Perforated Suede
There are different ear pad options when ordering the Aeolus on the ZMF website. Universe Pads are the stock pads that come with the headphones, which have the warmest tonal balance. ZMF recommends two other types of ear pads: Universe Suede and Vérité. The staging seems a bit larger, and the reverb effect is greatly reduced. The timbre of the instruments remains natural, but leans toward the warm side slightly. I highly recommend ordering the universe suede pads, despite the USD$60 price, which isn’t cheap for a pair of pads, but can be forgiven considering the materials used.
Comparisons
Audeze LCD-2 (Classic and Fazor)
I have much experience with both of the LCD-2 models; between them and the Aeolus, it’s a hard choice. But my pick is the Aeolus – it offers a greater timbre, especially in the midrange, more satisfying mid-bass slam, and better dynamics. As I mentioned earlier, I am not able to tell if the Aeolus pair are wider sounding than the Audeze or not. The Aeolus is a bit more expensive, but I would stretch my budget and buy them over the LCDs. The Aeolus is a better all-rounder, and offer more versatility with the different pad choices, going from dark/warm (stock pads) to neutral/warm (suede pads). The Audeze has clearer bass, along with more extension below 40 Hz.
Focal Elex
The Elex and Aeolus are my current daily drivers in the >USD$500 range (besides an HD800 I only use for gaming). The Elex is an amazing pair of headphones for USD$700 (or even less than USD$500 for a used pair), but it still sounds different from the Aeolus. The Focal is quite a bit brighter and leans toward a more “reference” tuning, with some peaks around 6 and 10 kHz. The bass is less elevated, with a gentle bump around 100 Hz. The upper-midrange is more forward on the Elex. In my opinion, the Aeolus beats the Elex in staging; both models have excellent dynamic range, while the Elex has a small edge in resolution and detail.
Kennerton Vali
The Vali retails for USD$1000 and is another wooden pair of headphones, from the Russian brand Kennerton. I vastly prefer the Aeolus to the Vali: better comfort and tonality (especially with the Universe Suede ear pads). The Vali comes with stiff leather pads, poor weight distribution, and suffers from a major lack of treble extension past 10 kHz and a weird (but not unpleasant) midrange tone. The Aeolus are better extended in the highs and offers a more realistic midrange presentation.
Hifiman Ananda
The Ananda is a decent value for USD$1000 (sometimes found for USD$850 brand new). The build quality is not its strong point and definitely far behind the Aeolus, but comfort is a bit superior – large oval ear pads and lighter weight. The Ananda exhibits a very balanced response, with solid bass extension, almost uncolored midrange (slight recession around 2 kHz) and sparkly treble. However, the Aeolus wins in the fields of natural timbre and dynamics, and is an overall more pleasurable listening experience.
Sennheiser HD800
It’s really hard to compare both headphones, since they are so different from each other; They could actually be amazing compliments. The HD800 is in another league in the soundstage and resolution departments. To this day, I still think they are the most resolving pair of headphones you can find for less than USD$2000 (they’re around USD$700 on the used market). The Aeolus will sound extremely dark, and possibly muffled next to the HD800. The Sennheiser is quite bright with a bizarre balance: upper midrange is recessed, and low-treble exhibits a nasty 6 kHz peak. It’s a much more clinical and fatiguing presentation.
Summary
The Aeolus has my top recommendation to anyone ready to spend around USD$1000-1200 on a high-end pair of headphones. I have no intention to sell my pair, and it will be tough to beat the features the Aeolus offers for the price.
