The ZMF Ori is a semi-open (85% closed, 15% open according to the website) planar magnetic headphone based on the Fostex T50RP MK3. One common concern I see is, how can a modded $160 headphone compete with the big dogs in the $1,000 price range? The answer: with ease.

It's one thing to have the biggest driver with the thinnest diaphragms and most powerful magnets in the world, but it's another to tune and voice a headphone. Zach from ZMF has mastered the latter, empowering these modded T50RPs (Blackwood and Ori) to be among the best sounding headphones I have ever listened to. And I have listened to the vast majority of popular flagships, and I own or have owned the following headphones:

- AKG K7XX
- Audeze LCD-4
- Audio Technica ATH-A900X
- Audio Technica ATH-W1000Z
- Beyerdynamic DT 880 Pro
- Fostex T50RP MK3
- HiFiMan HE-560
- LFF Code-6/Code Sex (modded HiFiMan HE-6)
- Sennheiser HD 598 Cs
- Sennheiser HD 6XX
- Stax SR-007A
- Stax SR-30
- ZMF Blackwood (another modded Fostex T50RP MK3)

Only one of those do I rank above the ZMF Ori personally for most genres: the Stax SR-007A (but I rank the Ori over it and all others for rap/hip hop). That's right, I rank the Ori (and Blackwood) above the Audeze LCD-4. It was actually the Ori that replaced the LCD-4 for me. You can find my review of it on the LCD-4 page here on Head-Fi.

https://www.head-fi.org/showcase/audeze-lcd-4.20951/reviews

Other flagships I prefer the Ori to are every Sennheiser (HD 800 / HD 800 S), Beyerdynamic (T1), Focal (Utopia), JPS Labs (Abyss AB-1266). I consider the ZMF Ori's sound to be less technically flawed than all of those. I personally enjoy it more than the HiFiMan HE1000/HE1000v2 as well, but I acknowledge how excellent those headphones are and technically superior.

But let's not beat that dead horse. My first ZMF headphone was the Blackwood. The Ori was my second. It will not be my last. Both headphones I purchased, blindly I might add (though one can hardly call the Ori a blind purchase when I already had a Blackwood). I rarely make blind headphone purchases, but these were worth every penny and then some. My audio chain is as follows:

• Breeze DU-U8 Digital Interface (I have also tried this configuration without this)
• Chord Hugo 2 (tested as just a DAC for the amp below, and also as a standalone DAC/amp)
• Mjolnir Audio Pure BiPolar
• Kimber Kable Hero Ultraplate RCA interconnects with Neutrik RCA to XLR adapters
• Norne Audio Solvine cable (Eidolic rhodium plated XLR) with the Pure BiPolar, ZMF Atmos C cable with Hugo 2.

Yeah yeah, I didn't list the stock cable. I've tried it plenty with the Blackwood along with the Atmos C, honestly I cannot hear a difference between the two. Perhaps you can, I cannot. I only got the Atmos C because I wanted a 4 foot cable.

For music genres, I primarily listen to various degrees of rock (e.g. Rage Against the Machine, The Doors, The Neighbourhood), different metal bands (e.g. Firelake, Chantry, Genitorturers), some late 90s and early 2000s rap (mostly Eminem and D12), and occasionally classical music and soundtrack music. I will also specify specific test songs I use for these reviews, and why I use them, later in the review.

About me: I am 24 years old and I just like music. My upper hearing limit seems to be around 19 KHz, lower limit might be just over 10 Hz considering my results with the Audeze LCD-4 (as good as it gets for headphone bass). I use this website for frequency tests. I maintain strong interest in the DIY community and believe in the work of people like Kevin Gilmore, Birgir Gudjonsson, Pete Millett, and companies like Audio Note, AMB Laboratories and HeadAmp. My favorite headphone reviewer ever is Tyll Hertsens. I believe in the objective and the subjective side to audio, so I don't believe in things like burn-in for electrostatic and planar magnetic drivers. I also firmly believe planar magnetic and especially electrostatic technology perform flat out better than dynamic, when implemented correctly. Both the objective and subjective have me believing that one.


That's enough of the boring stuff. Now the real reason we are here: the ZMF Ori. It is available in various wood options, you can customize the slider colors and the coin design/color. You can also get a very nice S3 Hardshell case with it for an extra $50.

My Ori has rose copper sliders, inset coin, and most of all the utmost magnificent purpleheart wood. It is one of the most beautiful headphones I've ever witnessed, a true work of art.

The pads are lambskin leather, thick and very soft. A suspension headband design is thoughtfully utilized by ZMF these days, it is simply the best design as it offloads much of the headphone's weight. This is important for these headphones since they are heavier than most. Planars are generally heavier due to the magnets, and wood is heavier than plastic, so we have a recipe for heft here! Never a problem though since the suspension headband design works perfectly. These headphones also don't have a strong clamp like say the Sennheiser HD 600 series.

The original T50RP MK3 headband seems to be the top one, with additional material wrapped around it. The inner headband is of ZMF's own design. I'm not sure of the exact material, but it's thick and dense. The headphone makes most others look and feel like toys, and makes me laugh at plasticky > $1,000 models.


The overall sound signature of the ZMF Ori is incredibly balanced. It's as forward as most other high end headphones I would say, like those from Audeze and older HiFiMan models. A comparison I like to make is, take the sound of Audeze's LCD lineup, remove the realism-hampering treble recession, and you've got something close to the ZMF Blackwood and Ori sound.

The Ori, like the Blackwood, emphasizes IMPACT but without drowning out the mids. Probably the most bass impact of any headphone that doesn't have severely recessed mids. The overall attack and PRaT for the Ori is incredible, making for one of the most fun headphones but without being fatiguing since it does not have accentuated treble.

This is what full bodied sound sounds like. Planars and electrostats can deliver this effortlessly, but it takes a special dynamic headphone to not sound thin in comparison (especially but not only in the bass, but I need to listen to the ZMF Eikon). You will also notice faster, more effortless decay leading to improved transparency with the ZMF Ori over most dynamic headphones. I commented about this in my Blackwood review, decay is even faster and more natural with the Ori due to it being semi open. Though higher end planars like the HiFiMan HE1000, SUSVARA, and Audeze LCD-4 will demonstrate this the best, and elite electrostats (Stax SR-007/SR-009/SR-009S) even better.

But let's break it down and get more specific:

Bass
World class. Extends as deep as any other headphone I've used including the Audeze LCD-4. My hearing is probably the limitation. I can hear the bass response close to 10 Hz in bass sweep tests. Sub-bass that a dynamic headphone can only dream of. The bass slam of the Ori includes the sub-bass as well, so you don't just hear mid-bass slamming like most "basshead" headphones, but the real deal. Breathtaking texture, transparency, and realism. Percussion sounds as if it is right there and you can reach out and feel it. Note that my Pure BiPolar amp improves bass considerably, in every way versus say a Schiit Lyr 3 with any tube (since I have the Lyr 3 on hand along with most beloved 6SN7 tubes).

The amount of bass impact is substantial when called for. It can rumble your dome, but doesn't try to force this in every song. It is just a very natural bass presentation that only a planar can do. The Ori (like the Blackwood) has harder bass slam than the vast majority of high end headphones, even among planars. I have listened to it side by side with the Audeze LCD-4 out of my Pure BiPolar balanced amplifier, and the Ori's bass is still respectable, thoroughly enjoyable, and breathtaking even next to the LCD-4. Yeah, the LCD-4's bass is even better (the best of any planar I've heard, but I still prefer SR-009 bass), but it doesn't outright crush the ZMF Ori (nor the Blackwood).

Compared to the Blackwood with one bass port sealed, there is a bit more mid-bass presence and seemingly more effortless detail retrieval, and the bass slam doesn't seem quite as forward as the Blackwood when both are slamming the most (rap music), but for this last point the difference is very mild. I believe this is all simply due to the Ori being semi-open while the Blackwood is fully sealed. I haven't thoroughly compared the Ori to any other Blackwood bass port configurations, but you can read my bass port configuration comparisons in my Blackwood review. With all bass ports open, the Blackwood bass is looser and less controlled but mid-bass presence will be closer to the Ori.

I no longer have the HiFiMan HE-560 on hand, but the ZMF Blackwood's bass outperformed it handily. Deeper extension, much better body and impact.

Compared to the LFF Code-6 (modded HiFiMan HE-6), the Ori's bass completely outclasses it. Code-6 is muddy in comparison, less extended with too little response in the sub-bass, seems to have an ever so slightly distracting dip in the bass to mids transition, and the Ori simply has more forward bass (slightly too recessed for me on the Code-6) with much, much more slam.

From my experience, the ZMF Ori is the king of rap/hip hop as far as headphones go. I've never heard better for these genres; not the Audeze LCD-4, not the HiFiMan HE1000, not the LFF Code-6, not the Stax SR-007A (though mine was only used with a KGSS). Bass to mids integration on the Ori is flawless. The mids are not at all drowned out by the bass, this is a high performance headphone not Beats after all.

Mids
The Ori's mids invite you in and keep you engaged throughout. Very linear, again an overall forward presentation. Vocals stand out even more than the Blackwood, supremely detailed and transparent! Sounds like you are in the recording studio with them.

One of my favorite songs to test is Sledgehammer (from one of the modern Star Trek movie soundtracks apparently). Rihanna's voice in that song sounds harsh and strident and artificial on probably > 95% of headphone systems. Even on the Sennheiser HD 6XX which is supposed to be laid back and never fatiguing (it is more laid back, just has some problems in the upper mids apparently). Slightly on the HiFiMan HE-560 too (less so than the HD 6XX). Not at all harsh or strident on the Audeze LCD-4 but that has its own issue thanks to the 4-8 KHz dips causing some odd immersion breaking recession (detailed in my review of it, which is here on Head-Fi). But the ZMF Ori nails it, like the Blackwood but with a more open sound and the other differences I've been describing. This is my favorite test song, if a headphone/speaker fails it then I don't want it.

It sounds to me like the upper mids of the Ori have a slightly stronger relative response than the Blackwood, also stronger than the HiFiMan Sundara and Audeze headphones for reference, but lower than the HE-560. I hear this most in Sledgehammer with Rihanna's voice, it sounds a bit closer than some other headphones.

Furthermore, every instrument sounds authentic, which means a lot to me since I absolutely hate unnatural instrument portrayal. Not the most detailed sound for non-percussion instruments; the Sennheiser HD 6XX has more detailed string instruments and more detailed/transparent pianos, but they are all authentic and enjoyable nonetheless.

Compared to the Blackwood, the biggest differences in the mids are again due to the Ori being semi-open, making for a generally "airier" sound due to there being less reverberations. It can make some details more obvious and natural on the Ori, most notably vocals and then string instruments.

Transition between upper mids and treble is flawless to my ears, something the aforementioned Sledgehammer song really tests well. Flawless, but without taking a step back. Audeze headphones and the HiFiMan Sundara will take a step back here to really avoid being fatiguing for example, making the upper mids sound a bit more distant than the lower mids. The ZMF Ori does not do this. Different strokes for different folks.

Treble
This is where most headphones fall apart. The unmodded Fostex T50RP MK3 falls apart here (and in the sub-bass region like a dynamic headphone). But not the ZMF Ori, likewise not the Blackwood. I still don't understand how Zach from ZMF transforms stock T50RP MK3 treble into this. Keep your "it's just a modded T50" generalizations at the door. The ZMF Ori has better treble than the vast majority of non-electrostatic headphones.

The treble is linear with no odd peaks or dips to my ears and zero graininess. It doesn't have a forward aggressive character, nor is it as laid back as my Sennheiser HD 6XX, leading to excellent PRaT and tons of fun for rock and rap. Zero sibilance, never fatiguing (and for those who care, remember I typically use a Norne Audio Solvine cable which has lots of silver content), doesn't sound excessively thin like a lot of headphones. A nice airy sound with surprisingly impressive detail retrieval! The difference aerodynamics make (thinking of the Blackwood as I type this part). The airier sound makes this headphone much, much better than the Blackwood for classical music.

The treble remains polite yet fun for dynamic music, as I said I listen to lots of rock including some of the heaviest, also metal and rap. The ZMF Ori (and Blackwood) are some of the most "fun" headphones for me, without the awful mid-range recession and brightness typically associated with "fun" headphones (I hate V-Shaped sound). The bass performance of the Ori and Blackwood are obviously major contributors, but so is the treble.

Something about the presence region causes the Ori to be the "sweetest" sounding headphone I have heard. More so than the Blackwood, I guess the semi-open nature reveals this more. Maybe it's a coloration, but everything sounds natural and effortless to me, and that sweet sound is incredibly engaging. Note my Pure BiPolar amp makes treble noticeably more clear and transparent.

Sound Stage and Imaging
Again, being semi-open helps a lot versus fully closed. Layering of instrument separation is better than the Blackwood, also note the balanced Pure BiPolar amplifier adds noticeable improvement here.

As with the Blackwood, I can't believe how precise the imaging is for what began life as a Fostex T50RP MK3. I don't need better imaging than this from a headphone. Sound stage is again presented in an overall forward manner but has noticeable depth and width, just a bit more open sounding with more effortless expansion of sound than the Blackwood but nothing overlaps when it shouldn't on either headphone. It images more precisely than the Sennheiser HD 6XX and HiFiMan HE-560 for reference.

Isolation and Sound Leakage
The ZMF Ori impresses me here too. It is 85% closed, 15% open. That 15% open makes for large improvements in sound, while the 85% closed still seems like 100% closed to me. I seem just as isolated from the environment compared to wearing my Blackwood, any difference here is negligible. Same for sound leakage - negligible difference. Looks like I don't require fully closed back after all.

Amplifier Pairing
The ZMF Ori still sounds great just out of a Chord Mojo, it's not like it becomes a totally different headphone. But you will lose a significant amount of impact, layering/instrument separation, and treble smoothness and clarity versus a top of the line setup.

The Chord Hugo 2 alone sounds exactly the same to me as the Chord Hugo 2 + the Schiit Lyr 3 with both the ZMF Ori and ZMF Blackwood. The Hugo 2 is a beast. But, compared to my Pure BiPolar, it is still missing a dimension of layering/spacing throughout the entire frequency spectrum, treble is noticeably less transparent, bass doesn't hit as hard and the Pure BiPolar introduces even more body to the bass (not that it sounds lean out of the Hugo 2 though).

So the ZMF Ori (and Blackwood) really scale well with top of the line gear. The Pure BiPolar amp (Super Symmetry Dynalo Mk2) and its sibling the HeadAmp GS-X Mk2 are perhaps the best amplifiers for 50 ohm planars such as these. It copes with the load effortlessly and, much to my surprise, elevates it to a higher tier. I thought the Schiit Lyr 3 or better yet a standard single ended Dynalo with a good power supply would be the end of the road for any Fostex T50RP, but I was wrong. Yes, I underestimated ZMF too.

Conclusion
I've cycled through so many headphones over the years. I don't foresee the ZMF Ori ever leaving my collection. It sounds too good, too well rounded, and on top of that it is such a marvelous piece of equipment. A beauty to behold, a work of art. The ZMF Blackwood will also remain in my collection, both for airplane use (and maybe road trips) and nostalgia. I have a soft spot for wooden headphones I admit, but even then they have to be excellent sounding for me to keep them!

At the end of the day, I listen to the ZMF Ori for hours at a time with no physical or auditory fatigue. It is difficult to put down due to its uniquely engaging sound presentation. A very rare blend of excellent sound in all frequencies for all genres, excellent comfort, outstanding build quality and gorgeous aesthetics.

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[color=rgba(0, 0, 0, 0.8)]ZMF Omni Review: Semi Open, All Entertaining[/color]

[color=rgba(0, 0, 0, 0.8)]This is the second ZMF planar headphone I’ve had the pleasure of auditioning. I was blown away with the sheer price-to-performance ratio of ZMF’s more tame headphone, the ZMF x Vibro Mk. II. Designed and hand-built by Zach Melbrach in Chicago, you can rest easy knowing one of the best sets of ears in business is responsible for your investment. However, does the law of diminishing returns hurt the value of the Omni, especially given the fact that the drivers are still from the T50rp Mk. III?[/color]
[color=rgba(0, 0, 0, 0.8)]You can find the Omni here starting at $899.[/color]
[color=rgba(0, 0, 0, 0.8)]Disclaimer: This review is based upon a loaner unit provided to me by ZMF in exchange for my honest opinion and un-edited words. I do not profit in any wayfrom the writing of the review. I would like to thank Zach for giving me this opportunity.[/color]
[color=rgba(0, 0, 0, 0.8)]Preference and Bias: Before reading a review, it is worth mentioning that there is no way for a reviewer to objectively pass judgment on the enjoy-ability of a product: such a thing is inherently subjective. Therefore, I find it necessary for you to read and understand what I take a natural liking to and how that might affect my rating of a product.[/color]
[color=rgba(0, 0, 0, 0.8)]My ideal sound signature would be an extended sub-bass with a leveled, but textured, bass. The mids should be slightly less pronounced than the treble, but still ahead of the bass. I prefer a more bright upper range.[/color]
[color=rgba(0, 0, 0, 0.8)]Source: The Omni was powered like so:[/color]
[color=rgba(0, 0, 0, 0.8)]PC Optical out -> HifiMe 9018 SPDIF -> 3.5mm out -> 3.5mm to 1/4in adapter -> headphones[/color]
[color=rgba(0, 0, 0, 0.8)]Hidizs AP100 3.5mm out -> FiiO A5 (high gain) 3.5mm out -> 3.5mm to 1/4inch adapter -> headphones[/color]
[color=rgba(0, 0, 0, 0.8)]Standard 3.5mm out from both my Nexus 6P and HTC One M8 was inadequate to drive the Omni.[/color]

[color=rgba(0, 0, 0, 0.8)]Sound Signature[/color]

[color=rgba(0, 0, 0, 0.8)]Initial Impressions:[/color]
[color=rgba(0, 0, 0, 0.8)]The Omni certainly exemplifies the essence of the ZMF house sound: smooth and warm, yet still articulate. The mids are well pronounced, but are behind the mid bass a bit. Treble is balanced well with the mids, and extends pretty far up. Bass extends well into the 20Hz-50Hz range.[/color]
[color=rgba(0, 0, 0, 0.8)]Treble: Songs used: White Flag, Midnight City, Outlands[/color]
[color=rgba(0, 0, 0, 0.8)]While many say that the Omni’s best feature sound-wise is the bass, I disagree. I find the treble to be the most impressive and well-tuned part of the sound signature. Allow me to explain. Firstly, the Omni is a warm earphone, through and through. However, Zach managed to maintain treble presence at all times, keep it dynamic and active within the mix, and smoothed it out, making it one of the least fatiguing earphones I’ve heard to date. This really shows itself in Midnight City, a song that makes heavy use of contrasting treble effects and deep bass lines. The treble effects had a hard edge to them without feeling sharp, which is indicative of a very healthy attack and decay in the treble.[/color]
[color=rgba(0, 0, 0, 0.8)]The treble kicked it up a notch in Outlands, becoming very expressive. I was simply blown away by the idea that the headphones I was listening to started out as a pair of plain old T50rps! I could pick out many more details within the violins, hearing the subtle differences in tonality between the various sections of the performers.[/color]
[color=rgba(0, 0, 0, 0.8)]Mids: Songs used: Flagpole Sitta, Jacked Up, I Am The Highway, Dreams[/color]
[color=rgba(0, 0, 0, 0.8)]For a warm earphone, the Omni does a great job portraying dry instruments like the drums within Flagpole Sitta. Furthermore, the Omni did a great job with instrumental separation and placement. The guitars had an electric crunch to them, the vocals sounded realistic and full-bodied, and the drums had a good “pop” to them.[/color]
[color=rgba(0, 0, 0, 0.8)]The pianos of Jacked Up had a good hardness to them, and sounded quite realistic in presentation, as the Omni managed to capture and display even the internal resonance of each piano within the mix, a feat I consider to be incredibly impressive. Needless to say, these headphones are the first ones I’ve tested that allowed me to hear the details within this song so clearly. There’s so much going on, and it really feels like the Omni is drawing you into the music. The bass guitar, lead guitar, rythm guitar, three vocalists, two pianos, and drums all resolve damn near perfectly. The guitar feedback is what really got me though. As a guitarist myself, I was shocked at how real it sounded through the Omni.[/color]
[color=rgba(0, 0, 0, 0.8)]The vocals of I Am The Highway were truly impressive. While still commanding of the song, they didn’t wash away any of the other instruments that happened to cohabitate their slice of the frequency response. They were clear but not hard on the ears. Most importantly, the vocals had a good timbre and presentation to them. While a bit warmer and thicker than I think is natural, it is charming in its own way.[/color]
[color=rgba(0, 0, 0, 0.8)]Bass: Songs used: Lights(Bassnectar Remix), Gold Dust, In For The Kill (Skream Remix), Leave Me[/color]
[color=rgba(0, 0, 0, 0.8)]I won’t lie: while Lights was definitely a fun listen, it really lacked the rumble I was hungry for. All the sound was there, but it just didn’t shake my head the way I generally want. But you know what? That’s fine, because if this is the sacrifice that needs to be made in order to maintain the level of fidelity the Omni currently has, then in my books, it is a sacrifice well worth its weight in gold.[/color]
[color=rgba(0, 0, 0, 0.8)]Speaking of gold, Gold Dust makes use of much more mid-bass than Lights does, and thusly had a decent amount of impact. Bass was tight and well-defined, but again, lacked rumble.[/color]
[color=rgba(0, 0, 0, 0.8)]Bass clarity and mobility is pretty good, allowing for songs like In For The Kill to make use of complex bass and sub-bass lines without muddying up the lower register. I don’t want to beat a dead horse, but I did miss the rumble I’d get out of my 99 Classics.[/color]
[color=rgba(0, 0, 0, 0.8)]Clarity: Songs used: Throne, Map of The Problimatique, I’m Not Alright[/color]
[color=rgba(0, 0, 0, 0.8)]Clarity is top notch, with no distortion at all across any of my test songs. Throne was presented smoothly, with only a small amount of missing detail in the upper register. I’m Not Alright also performed well, with the Omni being able to render almost all of the song, missing out on only a couple micro-details.[/color]

[color=rgba(0, 0, 0, 0.8)]Packaging / Unboxing[/color]

[color=rgba(0, 0, 0, 0.8)]I did not get any packaging, as this Omni is Zach’s showroom unit. It was shipped to me in a plain seahorse case, which is built like a frigging tank. If you do choose to buy an Omni, get the case. The peace of mind you get with it is well worth the extra charge.[/color]

[color=rgba(0, 0, 0, 0.8)]Build[/color]

[color=rgba(0, 0, 0, 0.8)]Construction Quality[/color]
[color=rgba(0, 0, 0, 0.8)]For a headphone that started out as a paltry T50rp, the Omni is certainly a thing to behold. Even this showroom unit, which has undoubtedly gone through a lot of handling, you can barely notice it’s extensive use. Everything from the head-band to the hand-stained wooden ear-cups of the Omni oozes premium, and you can easily tell that these are things that were built by caring hands.[/color]
[color=rgba(0, 0, 0, 0.8)][/color]
 
[color=rgba(0, 0, 0, 0.8)]The cables are also pretty nice, and fit snugly into the Omni. They detach quickly and easily, but never by accident.[/color]
[color=rgba(0, 0, 0, 0.8)]Comfort[/color]
[color=rgba(0, 0, 0, 0.8)]The Omni is very heavy but is not uncomfortable on the head due to ZMF’s great headband and earpads. The only point of contention I had was on my first three hour listening session where my neck began to hurt a bit. However, after another day or so I did not notice any more discomfort, no matter the duration of my listening session. People with smaller heads will certainly have issues maintaining a snug fit though. While better than the Vibro Mk. II in terms of clamping power, I still found the Omni quite easy to dislodge from my head with semi-normal movement. Thusly, I find the Omni to be great for still listening-sessions, but less than ideal for any on-the-go listening.[/color]

[color=rgba(0, 0, 0, 0.8)]Summary[/color]

[color=rgba(0, 0, 0, 0.8)]The Omni is an homage to Zach’s dedication to his craft. For $899 you get to customize the Omni to look exactly how you want, with a sound that you are pretty much guaranteed to enjoy. However, I am still a little unsure about spending so much on a modded T50rp, built by Zach or not. The quality of the build is undeniably good, but I can’t help but think that these drivers are certainly holding the Omni back. If Zach could introduce a dynamic headphone at this price-point with similar tuning, I’d recommend it in a heart-beat. Congratulations on building such a great headphone though Zach.[/color]
[color=rgba(0, 0, 0, 0.8)]Once again, I’d like to thank Zach at ZMF for lending a pair the Omni for this review.[/color]

 
Omni. From Latin origin it means something like “all, every, of all things, the whole.” To date, The Omni is the whole of ZMF Headphones. It’s the flagship offering; it’s the pinnacle of what Founder Zach Mehrbach’s constant tweaking and dissecting of a headphone in every way can yield.

At ZMF Headphones, every headphone is assembled by hand, tweaked, tuned and sent out by Mehrbach, a painstaking process I’ve been privy to see firsthand on several occasions. In full disclosure, I first met fellow Chicago local Mehrbach some years back as a disappoint ZMF x Vibro owner. I had mentioned some complaints on a popular headphone forum, and, in standard ZMF customer service fashion, Mehrbach was quick to personally message me about my issues and offer a solution. He takes his products seriously, he stands behind them, and he is simply a stand up guy. This has led to a true audio acquaintanceship between us. I’ve seen the inner workings of ZMF Headphones. I’ve been invited to demo and critique countless prototypes. And, I’ve been able to see the culmination of Mehrbach’s work result in some truly fine products that headphone enthusiasts around the world enjoy. So when Mehrbach offered me the opportunity to do a long-term review of The Omni, I was happy to welcome them into my home listening room.

The Omni is the result of years of fiddling, research and design between ZMF Headphones and Vibro Labs. Like the ZMF x Vibro (see my coverage), The Omni is built around the latest generation of Fostex’s T50RP driver and cannibalizes some of its suspension parts. The Omni, however, uses an all-new, semi-open, 100-percent wood cup that’s hand finished in-house. And, true to its name, The Omni aims squarely at doing everything well. ZMF Headphones has always been about customization, so there are eight different woods to choose from—all of which have their own subtle personalities—a couple of headband, slider and emblem options, and various cables to choose from that make each order unique to its prospective owner.

My review unit uses ZMF Headphones’ own angled leather pads (these fit on many headphones, and I highly recommend them), African Blackwood cups, pilot pad headband, and DHC copper litz balanced cable. The African Blackwood did wonders for the ZMF x Vibro. It’s a beautiful and very dense wood that leans to the dark side while still being fast and resolving, so does it do the same for The Omni?

First Listen

Smooth. Powerful. These were the first two words I could think of to describe The Omni when I queued up Moderat’s track “Bad Kingdom” for my first listening test. The sub-bass and overall bass extension is literally some of the best in the business. I’ve owned premium headphones from Audeze, Beyerdynamic, Hifiman, Fostex and Sennheiser, and no other has come close to producing the feeling of the SPLs hitting my ear drums like The Omni. The bass is thick and rich; it oozes like honey, but it’s not slow like molasses. It simply hits hard and fast and leaves its impact on you. If you’re a basshead, The Omni is to die for. The textured bass in “Bad Kingdom” is heavy and complex, it can make or break a headphone for me, and it makes The Omni. 

Despite the bass being the clear dominator in The Omni’s sound signature, there’s no muddiness, it’s not boomy, and somehow it refrains from sounding closed in. You’d think that The Omni’s mostly closed-back (semi-open) design and emphasis would crush its soundstage, but its atmosphere extends surprisingly well to what seems like a few inches beyond the headphone. I’d say The Omni’s dimensional soundstage is somewhat comparable to that of the Fostex TH-600, which I think extends very well for a closed-back headphone, and the Sennheiser HD650, which has a more intimate soundstage despite its fully open-back design. 

Intimate is also what you get as The Omni’s oomphy basslines blend into its smooth midrange. The Omni won’t let you Flea the prominent basslines (get it, get it?) in the Red Hot Chili Peppers’ album title track “The Getaway” or hit “Dark Necessities,” but Anthony Kiedis remains front and center with his smooth vocal tones. Tom Toms and guitars are projected well with full-bodied resonance and twang. For jazz tracks, like Matthew Halsall & The Gondwana Orchestra’s "Ode to the Big Sea," The Omni sings out with a full, sweet sound that’s smooth on the senses. 

The one sense you may feel from time to time is that you’ve lost some sizzle in your sound. The Omni is notably dark compared to many hi-fi headphones. While the treble it has extends well and captures enough resolve, it’s the treble that it doesn’t have that you may miss from time to time. As the treble smoothly drops off, The Omni loses some sense of space and instrument separation as well, but at the same time it works wonders for taming the unruly treble that’s become all too common in modern music. The Omni truly offers a reprieve from the loudness war; it’s a savior of ****ty rock recordings that are too sizzle and sibilant happy. 

Sibilance is something you’ll never have to worry about with The Omni. Its relaxed tonal balancing favors those looking for enveloping bass and mids. What The Omni does, it does well. But how does it stack up to some of the competition?

Quick Comparisons

The Omni’s place in the market falls somewhere between the likes of Audeze’s LCD line and the ever-popular Sennheiser HD650. In comparison to the Audeze LCD-X, which has been my reference headphone for quite a while now, The Omni makes the LCD-X sound bright. This was a startling surprise for me. In general, Audeze LCD headphones are lush and dark, even the more balanced X. While The Omni and LCD-X share similar traits in being bass and midrange masters, I feel that The Omni has far greater bass emphasis. It hits harder and deeper, but feels less controlled. Throughout the mids, the X seems to pull out more details and textures, especially on jazz tracks where it easily bests The Omni in instrument separation, placement and clarity. The highs are where these two headphones diverge even further. Both have notably rolled off treble, but The Omni sounds even more rolled back because of its strong bass emphasis, as if it completely glances over the treble. Here the X pulls ahead again, offering better detail retrieval and more edginess on cymbals, strings and horns. It’s important to note that these are observations while switching back and forth on single tracks. While listening to one or the other for an extended time, your ears become accustomed to the sonic signature, so the differences become less apparent and you can simply enjoy the music. And I assure you that both of these recreate music very well. While both are heavy headphones, I’d say they’re about equal in comfort. I think the ZMF pads are actually plusher than Audeze’s, but I don’t get the same hotspot on the top of my head while wearing the X. Your results may vary. Both share the same cable terminations, so if you have an LCD model, you can use your cable on The Omni, which is nice if you have custom cables. 

I feel like Sennheiser HD650 or Fostex TH-600 owners may look to The Omni as their next step in the pursuit of Audio Nirvana. The biggest consideration among these three is the sonic signature that you favor. The HD650 is a classic—it has a very analog and intimate sound with an enhanced upper bass and midrange that is often described as being “romantic.” The HD650 and The Omni flat out sound very different. The Omni across the board is far smoother, exhibiting none of the grain or edge that the HD650 has. The Omni’s bass is deeper, smoother and more impactful. Like the HD650, The Omni offers rich mids, but they are tonally different. Here again, The Omni is smooth and effortless whereas the HD650 pushes vocalists right into your face. As for the treble, the HD650 has some grit to it, it can be sibilant at times, and it doesn’t tame poor recordings. Well, The Omni, as you know, is the opposite of all of that. With either headphone you will experience an intimate and enjoyable performance. The Omni does everything better to my ears, but the presentation is also very different. The HD650 is supremely comfortable and is easier to amp in my experience. But if you have an amp that will drive The Omni well, it’s definitely worth giving your Sennheisers a run for their money.

I mention the Fostex TH-600 because it’s a staple for bassheads and Massdrop’s collaboration models have expanded its popularity. Without question, The Omni hits harder, deeper, cleaner and more controlled. The TH-600 is very U-shaped in its sonic signature, meaning there’s bass and treble and the mids get left behind. The Omni excels at transitioning from bass to mids and delivering all of their lushness to your ears. You’ll gain a lot of musical body by upgrading to The Omni without sacrificing the bass you love. You’ll simply get better bass, better mids and, oh yeah, better treble. The TH-600 has sibilant and grainy treble. The Omni knows better. I listen to a lot of electronic, downtempo and EDM music; the TH-600 was a fav of mine here, but The Omni takes the cake now. Again the TH-600 is a very comfortable and lightweight headphone compared to The Omni, but the sonic improvements are worth experiencing. The Omni and TH-600 have similar reach and dimensionality in the soundstage to my ears, but still The Omni edges out the TH-600 in the end. 

The Caveats

Power and pleasure. What I mean by that is that The Omni craves power and, depending on your penchant for heavy headphones, may or may not be a pleasure to wear. 

The Omni isn’t quite as current-craving as the notable Hifiman HE-6, but it most definitely needs power to perform best. On my Eddie Current Balancing Act, I typically listen to my Audeze LCD-X and Sennheiser HD650 around the 10 o’clock mark on the volume dial; The Omni had me cranking it up to about Noon-thirty or one o’clock to make them sing. I also have the powerful Hifiman EF-6 class-A solid state headphone amp, and The Omni required the dial to reach about 11 o’clock for comfortable listening. In my experience, both The Omni and ZMF x Vibro mate best with tube amps. There’s just something about the synergy there that takes the performance to a more holographic level. 

About that pleasure factor. The Omni and its plush leather pads wrap your ears and smother them like a warm blanket—in other words, very comfy. They do a great job at supporting these beauties that weigh in at 568 grams. In comparison, the HD650 weighs a mere 263 grams and the clunky LCD-X weighs 618 grams. My one issue is really with the headband; even with the pilot pad I get a large hotspot on the top of my head. It’s worth mentioning that my small head may not be best for weight distribution, and the headband can be bent into different positions (carefully), but I simply made due. Of course, the leather suspension strapped headband is also an option to consider. 

These two caveats aside, The Omni has little else to detract from it.

Final Word

It goes without saying that The Omni in African Blackwood is a dark headphone, and dark is beautiful to my ears. The Omni delivers on its promise to be dense and resolving. The bass is tight and powerful. The mids are smooth, lush and intimate. The treble, while relaxed remains resolving to a hi-fi degree. The Omni will not be all things to all people as its namesake implies. But, in all, The Omni makes you privy to a sweet, full-bodied powerful performance time and time again. Figure that one out.