Edit: I bought a Schiit Magni 2 just to see how it sounded with clean amping and the sound has greatly improved. The Asgard, though I love how it sounds with my other headphones, isn't the best match for the Vibro. It needs a clean signal for it to shine.
 
Zach’s blog on his fascination with wood, its properties and how it can be utilized by man is a good read.I recommend you all to check it out. The man uses the resource on his products in a way that blends both aesthetics and sound in the best way imaginable. This, of course, goes beyond the Vibro – check out the Blackwood and Omni models and how picturesque they are. Due to the use of wood, each pair is unique – which lends a sense of ownership that indiscernible factory designs from other manufacturers can’t reproduce.

I was introduced to ZMF headphones by a friend of mine who had just recently purchased a Fostex THX-00 from Massdrop. He was absolutely in love with the sound but was looking for something to complement his repertoire of headphones. He fully recognized the V/W shaped sound of the THX-00 and wanted something more neutral. However, he didn’t want to lose the bass impact that the Fostex gave him at the same time. After looking around, he showed me the ZMF website and told me about how it’s a small-scale business run by some guy named Zach Mehrbach. I’ll admit, I didn’t quite grasp how the idea of tonewood (something I was familiar with as I have two acoustic guitars on hand specifically for their different wood and the sound difference) could translate to headphones. I thought the designs looked neat though, especially the Omni cups.

My friend soon got himself a pair of Blackwood Omnis, the top of the line offering by ZMF. It seemed he had finally found what he was looking for, neutrality without the cost of “fun.” I had owned a neutral pair of headphones once, recently sold, in the form of the Sennheiser HD600. I enjoyed it for vocals, but the bass wasn’t to my liking. I had looked into Planar Magnetics and managed to find an excellent deal on a new Hifiman HE400i due to a friend visiting Beijing over the winter. It quickly became my favourite pair and motivated me to sell both my HD600 and Beyerdynamic DT990 as I felt it blended and superseded what I enjoyed about both cans. With a little spare cash, I set out to see for myself what the ZMF hype was about.

I went for the Vibros because I wanted to experience what a truly “fun” headphone would sound like without attempting to be anything but that – at no cost of mids. I’m not bass-head, but I wanted bass. I read that further up the line, ZMF headphones tended to be a bit more laid back and I wanted none of that. Also my budget could only allow for a Vibro so hey I’ll happily take what I can. I’m glad I took the plunge, but I won’t be getting rid of my HE400i and this is why:

The Vibro is warm, very warm. “Dark” is a word that has been used to describe it and I don’t disagree. The Mk. 2 is described to extend the treble, but I haven’t heard one so I cannot say. Before I analyze what I hear and like about the Vibro Mk. 1, I will plainly state that if you only listen to certain genres of music like pop, rap and EDM – this should be your go-to set of cans at this price point. However, if you’re like me and listen to a vast array of music – you want another pair to round off your collection that can handle the genres and recordings that the Vibro has difficulty with.

Consider an aggressive genre like metal. Now consider an aggressive metal band like Slayer. When you listen to Slayer, you want all cylinders to be firing on whatever audio system you have. You wouldn’t enjoy it as much if something fell short. I’m glad to say that the Vibro doesn’t fall short in this regard. The cherry cups and planar magnetic drivers combine to give sheer power to whatever you are listening to. This is not a laid-back set of headphones at all. It pushes the music out at you in a bombastic manner that makes you take notice of everything you hear – and most of the time you can hear it all clearly.

If you have a song you really like but can’t stand how sibilant it can sound at times, this is the pair of headphones for you. If you have an album you wish had a bit more kick to it, these are the headphones you should listen to it with. If you want to kick back and listen to some progressive rock, these probably aren’t the headphones for you – which is why I’ll be keeping my HE400i. The treble roll-off on the Vibro is reliant on what you’re listening to – both recording wise and genre wise. For pop and rap, it isn’t even noticeable 90% of the time. For soft rock, it’s quite noticeable and can feel a bit stifling – particularly with the likes of Pink Floyd. If you enjoy listening to vinyl rips, unless they are super clear and equalized, you might not enjoy them on this. EQ itself is something I tend to not use very much but I would recommend it to listeners who find the treble roll-off to be a bit too much. I, personally, will just switch headphones whenever I’m in the mood for genres this isn’t the best for.

However, if you’re listening to something that fits well with the Vibro’s sound signature then there isn’t anything like it in this price range. You’ll find yourself switching the bass ports depending on your mood and genre you’re listening to – but keep a close eye on where you put the little rubber plugs because it’s very easy to misplace them. I personally have two plugs in most of the time, with only one plug in for pop/rap and no plugs in for electronic music.

I have to give a shoutout to Zach for his work with his headphones on behalf of myself and my friend who owns the Omni. I would absolutely recommend peering into his product line to anyone looking to get into “fun” high end audio. This isn’t the realm of the HD800 and its benefits. This is the realm of musically-tuned drivers encased in sexy wood that is uncompromising in its identity and market niche.

The Procurement Process:
 
Being a student and all, I could barely afford a fresh pair of Vibros straight from the factory. Plus, my impatient ass didn't want to sit around waiting for a 2-3 week shipment. As luck should have it, a fellow "carouseller" (an ebay clone created locally for Singapore) advertised an almost mint condition ZMF Vibro (specifically the Massdrop Galaxy Edition Purple) at approximately 360 USD. Without hesitation, I sold most of my current headphones/iems (Beyerdynamic Custom One Pros, Noble 4+ Silver Dragon Cables) to fund this purchase. Fostex Mods are hard to come by in Singapore and having little to no experience with planar-magnetics, I decided to pick up these little curiosities.
 
 
 
General Information:
 
ZMF (an abbreviation for Zach Mehrbach Films), is a side project opened by a guitar manufacturer, Zach Mehrbach. Fond of music and pursuing the craft of good audio, he decided to use his work experience with wood and its resonant properties to create "Franken-headphones", utilizing modular parts (padded headbands, lambskin earpads, different cable terminations, tunable open-bass ports). The consumers can opt for different terminations, wood type + finish, earpads and headbands etc. His wife also offers the service of handcrafting various cable upgrades that can be purchased alongside the headphones themselves. Zach often frequents various threads on Head-fi, interacting with the general crowd on the forums.
 
From the looks of it, this is much more than a passion project. 
 
This particular model is circum-aural, utilizing the infamous Fostex T50RP drivers with added damping, a completely new sound signature and CNC'ed Cherry Wood Earcups that supposedly improve the dynamic response of the headphones. They're also fitted with Pilot Headbands and Lambskin earpads. They come with a standard 1/4 inch jack terminated cable, with Audeze style connectors (mini xlr's). Their rated impedance is at 50 ohms.
 
 
 
Initial Impressions:
 
The first thing that I noticed was the size of the entire package. The non-descript white cardboard box (with a ZMF sticker) was rather wide. Lifting up the front lid of the box, I was greeted by a pair of chunky beasts. The headphones are fitted with ZMF's famous Pilot Headband and Earpads made out of Lambskin. Most of its size comes from the solid padding for extra comfort. 
 
Out of the box, the package includes the headphones themselves, more than sufficient bubblewrap, a satin carrying case (don't know why you'd want to carry these gargantuan headphones out) and a certificate of authenticity (complete with serialized numbers and the date of manufacture). I would've expected a Pelican hard-shell case if I paid full price for them. Considering I purchased these at a significant discount, I sure as hell can't complain.
 
The Purple Cherrywood Earcups are reminiscent of exotic furniture from luxury brands. They have a similar alluring charm that draws people to its distinct appearance. A few blemishes and an imperfect surface make them look more natural and less artificial than a crapty piece of machined chipboard. Replacing the plastic earcups was a brilliant idea that stood out from similarly priced competition (MrSpeakers, Mayflower Electronics). 
 
The heavily-padded headband (Pilot Headbands) and the 2-3 inch thick Lambskin Earpads adds a needed comfort for long listening sessions. The headband effectively balances the weight of the entire headphone across the skull effectively. They clamp with just enough force to provide a snug fit on the head. Understandably, Planar-magnetic headphones are often heavy and outlandishly big. Don't get me wrong, these are WAY larger than your run-of-the-mill pair of headphones. These are cantankerous and some would be put off by its "not so subtle" profile. I am happy to report that the weight does not affect its listening comfort. I wear them for over 4 hours (gaming+ music sessions) on a daily basis, free from ear-fatigue or a sore head (from the clamping force). From my 2-3 months of using these headphones, I can easily vouch for their comfort. 
 
With regards to the build quality, I'll let this "durability test" video speak for itself.
 
https://www.youtube.com/watch?v=odQUqnOKGl8 
 
 
 
Sound Quality:
 
Setup used: Aune X1S + ZMF Vibro Mkii + Foobar 2000 v1.3.6
 
Smooth and intimate, the natural sound of the Vibro Mkii is bound to attract an audience. They sound lush and intimate, with a "front row" sound-stage that immerses you in the music's forefront. Instrument separation is substantial enough without sounding incoherent. They especially shine on jazz recordings or female vocal tracks. Diana Krall's California Dreamin was an exercise in perfection. Her smokey voice, the glint from the violin section and a tightly strung bass almost sounded like a live recreation of that specific track.
 
Most importantly, the purchase of this modified pair of Fostex T50RP (retailing at approximately 180 USD) is definitely justified. Sounding unlike its little brother, the Vibro's are slightly mellower, with a cloudy sound that exercises control on the treble and sibilant high frequencies that can cause excessive ear fatigue. Do not be fooled by my previous statement. The Vibros have more than sufficient detail without the dry harshness commonly associated with crystalline highs and realistic treble. They pump out an assertive bass section, with incredible mid-bass speeds and just enough sub-bass for those who prefer a leaner low-end. Do take note that these headphones aren't for bassheads looking out for sub-woofer levels of crazy. The mid-bass decay is too fast and rigid to be called a basshead's dream. 
 
Alas, there is so much one can do to push headphone drivers. The Fostex T50RP drivers has a tendency to lack ultra-low frequencies. This was noticeable on the ZMF Vibros, with a strange lack of sub-bass decay and natural slam. To be fair, these drivers have their limits and there's only so much one can mod. 
 
For customization and all its intended purposes, the headphones has 3 tunable ports on each earcup. Rubber stoppers can be inserted into these ports to close and open the sound. In my honest opinion, this only affects the sound-stage significantly, with minor differences to the bass and treble regions. The summaries are as written below.
 
No Ports Closed => Semi-open Sound-Stage, Lush Bass Section, Slightly Masked Treble
One Port Closed => Less open Sound-Stage (compared to previous configuration), More Control on the Bass, More Treble Detail
Two Ports Closed => Less open Sound-Stage (compared to previous configuration), Bass becomes more intimate, Treble is alittle more Brittle
Three Ports Closed => Closed but more forward Sound-Stage (compared to previous configuration), Bass is more "in your face", Treble gains slightly more detail
 
 
 
All ends well
 
Even with its few caveats, the ZMF Vibros are easily the most engaging and musical pair of planars to ever come by. These are purposefully made to be as inviting as possible. Even at full price, these headphones are definitely comparable to the likes of higher end planar magnetic headphones (Audeze EL-8, Hifiman HE400i etc.) If they were paired with a reference amplifier/dac section with ample juice, these headphones will definitely shine and show its vast potential. Here is a poorly done shot of my pair (I suck at picture taking, my apologies):

 
Pros: Comfort, build quality, sub-bass quality, multiple sound tunings.
Cons: Shouty upper mids
Tonal Balance: Warm to balanced depending on ports.
Style: Closed over-ear
Listening Set-Up: Musicbee (FLAC) -> Matrix HPA-3U
Cost: Starting at $499
 

Reviewing Process

I’ve had the Vibro for about a month and during the time I’ve used them to skype, play League of Legends and to listen to a wide assortment of music. During my time with them I feel that I’ve become comfortable enough with their sound and build to comment on them fairly. With that said reviews never trump experience and I encourage readers to demo products before buying them when possible.
 
Thanks Zach at ZMF for letting me review these!
 

Build & Fit

 
Build
The Vibro are a highly modified Fostex T50rp mod, so much so that they’re barely recognizable as the T50rp outside of the headband and the adjustment sliders. Zach has reworked the aesthetics in collaboration partly with Luke over at Vibro Labs who makes the beautiful wooden cups for this line. The wooden cups are finished with care and precision, these being constructed of beautiful red walnut, with 3 bass ports that allow for the user to change the sound signature of the Vibro, but we’ll talk more about that later.
 
The Vibro features a choice of two straps, mine shipped with a leather strap that is thick, cleanly cut and secured soundly to the headband. The pads are new and now made of lambskin and they look as great as they feel. The last big change to the build is the removable cable, now a dual XLR instead of the single locking 3.5mm the T50rp once had. The connectors sit firmly attached to the headphone and the attached cable feels sturdily built.
 
Based on this pair I feel safe to say that Zach has put a lot of time and care into modifying the looks of this while keeping the build quality up to par. Luke’s cups are beautifully crafted and they’re certainly a conversation starter when I have friends come over.
 
Fit
The Vibro are now shipped with angled lambskin pads that are super plush and super comfortable. The pads feel uniform in height and firmness as they form their seal around my ears. Clamp is moderate, not enough to headbang, but they won’t just fall off willy nilly. Downwards pressure is mild, though certainly noticed as the wooden cups and planar drivers add some heft to the headphone. The Vibro never disappear from my head, but I have worn these for 3 hours with no issues. Isolation is phenomenal though, noise stays in even when listening on the loud side with no bass ports closed.
 

Sound Quality

Preface: This portion of the review will be written from the perspective of having no bass ports closed. There will be a short write-up for the change in sound with the ports closed below.
 
TLR
With stock bass ports the Vibro are v-shaped headphone that packs a serious punch in the low-end. The sound is layered wonderfully with great imaging capabilities, a joy to listen to the likes of James Blake with while sounding competent for everything else I’ve listened to.
 
Bass
Using the bass shaker test at the Ultimate Headphone Test page the Vibro are capable of deep sub-bass response that sounds near linear, with a small dip before the mid bass, but nothing alarming.
 
In real world listening, soulful electronic music absolutely shines here; sounding incredible with James Blake’s self-titled debut as well as Jamie xx’s debut In Colour, for example. Both albums highlight the silky smooth sub-bass in presence, impact and speed. That isn’t to say that the sub-bass is super fast, but it is quick enough to keep up with James Blake’s Limit to Your Love. The sub-bass is thick, which creates a slightly sluggish sub-bass response, while offering a pleasant rumble that brings Jamie xx’s Sleep Sounds to life. The sub-bass isn’t the end-all be-all, it lacks control at times, but it sounds phenomenal for the dreamy bassy music of these two UK electronic stars.
 
The midbass is certainly prominent but less so than the sub-bass, with the bass sounding as if there were a mild downward slope from the sub-bass to the midbass. With that said the midbass is thick and syrupy with a bit of bloat into the midrange, powerful and punchy but overly present at times. Pop music sounds phenomenal with the added midbass thump, as does the variety of electronic music that I’ve tested. In-fact anything danceable benefits from the added umph in the midbass. The midbass is pushy and bloated though and the tunes of Steely Dan sound too thick in the lower-end at times and throw the song off balance.
 
Stock, the bass is tuned to be emphasized, adding thickness and impact. I find the tuning to excel with bass heavy tunes as well as dance hits, while sounding overly present otherwise.
 
Mids & Highs
The midrange is lush and thick in the lower regions, emphasizing and adding warmth to lower ranged vocals, acoustic piano and tom hits on acoustic drum kits. The lower midrange suffers from a bit of grain as well as midbass bleed, causing a sense of recession in the lower ranges while also masking detail in this range. The midrange leans natural sounding though, even if a bit syrupy, reminding me a bit of a thicker HD600. Clarity and detail are sacrificed for warmth and thickness, which falls in line with my preference of bass heavy electronic music with the Vibro.
 
The uppermids become a bit shouty, noticeably in upper vocal ranges as well as the snare drum. The shouty vocals are most apparent with female vocals, though Pink Matter by Fank Ocean sounds overly forward at times as do some other more powerful male singers. The higher frequencies are tamed and done rather well though, sounding smooth and balanced while having a hint of sparkle throughout.
 
Presentation
The soundstage is intimate while having a good sense of stereo imaging, layering and depth. Instrument separation is decent, but held back by the thick lower end which takes up a large portion of the soundstage at times. The Vibro are closed headphones and certainly sound it in how they present the sound, not as closed as something like the M50, but certainly no K701.
 
Bass Port Options
Preface
Since it’s a bit difficult to go back and forth in a timely manner due to the nature of inserting and removing the stoppers I can not easily go back and forth between tunings. The thoughts expressed here are done by memory and could be a consequence of expectation bias. I am sharing these thoughts in good faith though and hope they are helpful.
 
One Port Closed
Stock I felt that the bass was overly assertive and undercontrolled, fun for certain genres, but too prominent enjoy more nuanced tunes with. With one port closed the bass significantly tightens up without sacrificing the powerful response that the stock tuning offers. If stock is a dark club with pulsating dance tunes, one port closed is a smokey jazz club with single malt scotch being poured generously. This tuning is smooth and sexy from head to toe, warm while lively, musical while nuanced.
 
With the bass tightened up the midrange and soundstage sound significantly more coherent. The midrange is still lush, but sounds cleaner and more detailed with a more natural tone throughout. In turn the soundstage also sounds cleaner with instrument separation benefitting heavily from the lack of low-end bloat. Listening to Lana Del Rey has never sounded as good and I keep wanting to reach for a cigar when a Steely Dan tune comes on, I’m in love.
 
Two Ports Closed
This tuning sounds really well balanced while maintaining a hint of warmth that the Vibro is known for. The uppermids are still a bit shouty, which will likely be common through all tunings, but I don’t find it overly forward. This tuning further solidifies my love for this headphone, adding further versatility to this headphone and solidifying it as a definite recommendation from me.
 
Three Ports Closed
At first I felt that this tuning was too mid forward and lean in the lows, but after giving my ears time to adjust I now feel that this tuning is the most balanced and natural of the four. By plugging up the last open port the soundstage sounds the most accurate and spacious of the bunch, while also sounding the cleanest from a sound reproduction stance. This tuning nears neutral to my ears and is quite versatile in genre compatibility. From 1970s Japanese fusion jazz to 2000s electrodisco this tuning is very capable.
 

Conclusion

The Vibro are the first new headphone in quite a while that have left an impression on me. I am astonished at the beautiful aesthetics, the sturdy build quality and the versatility of the sound signatures. All in all the Vibro are the total package for someone looking for a closed headphone within the $500 price range and they receive a full recommendation from me.