ZMF Eikon Sealed Around-Ear Headphones

On the one hand you have Sony, Sennheiser, AKG, and the like mounting big bucks R&D efforts to grab at the various brass rings in the headphone world; and on the other hand you have a guy like Zach Mehrbach, Founder, CEO, and Chief Cook and Bottle-Washer at ZMF Headphones, who's artisanal approach is less mental and measurement, and more heart and art...lots more.

ZMF is best known in headphone enthusiast circles for their modified Fostex T50RP models. Personally, I've always felt the T50RP never quite lives up to the energy put into it by DIYers and small shop manufacturers. And it also comes with the downside of being very inefficient and hard to drive with a portable rig. Zach, of course, is very familiar with the limitations of the driver, and I was tickled pink at last year's RMAF to hear of his upcoming Eikon and Atticus headphones sporting more traditional dynamic drivers.

ZMF Eikon ($1299 in Cherry, $1399 in Padauk)
The Eikon is a big, sealed, over-ear headphone weighing in at a beefy 586gr. sans cables. Large wood earcups dominate the styling of these cans, which is unapologetically functional, done with a deft hand. The Eikon is available in both Cherry and Padauk woods. Zach says there is a very small difference in the sound between the two, but woods should be picked primarily on their aesthetic attraction.

The main headband arch is a leather covered metal band with an inner leather suspension strap. The inner strap is ever so slightly shorter in length than the main headband allowing it to float just barley touching the outer headband and conforming exactly to the shape of my head. I found this unusual system quite successful at distributing the significant weight of these headphones over a large portion of my head and making them a surprisingly comfortable fit.

Supple black leather covers the memory foam of the ample earpads. Openings are generous at 69mm x 49mm, and deep enough that my ears don't touch anything within the cups. Caliper pressure is spot on for me. The Eikons fit quite well for a headphone of this weight, but they are rather warm in long listening.

Earpad angle adjustment is quick and easy with earcups rotating forward and aft on large stainless steel pins rotating in machined holes in the aluminum headband ends; and up and down on setscrews on either side of the bail. Headphone size adjustment is also done with the stainless steel pins moving up and down in headband end-piece. There is quite a bit of friction here and this adjustment is somewhat difficult; but once set it remains surprisingly well in place.

The Eikon comes with a large durable plastic carry case, and numerous cable length and connection options are available at time of purchase.


At the heart of the Eikon is a 50mm dynamic driver with bio-cellulose fiber diaphragm and rubber surround. Past experience has me believing that this type of driver is much more likely to deliver excellent sound when compared with typical thin plastic diaphragms, due to the stiffer cone leading to a more pistonic motion and less modal break-up at high frequencies.

I have to say at this point that while my past experience with fiber cone diaphragms has exhibited plenty of promise, few have been able to deliver on that promise. Maybe, just maybe, it's because most manufacturers refuse to put damping materials in the headphones behind the driver. No so ZMF.


DIY headphone enthusiasts have long modified headphones by adding damping materials and know first hand what a difference it can make. ZMF Headphone was born in that world, and Zach has become a master at damping headphones over the years.

The two most obvious pieces of damping material are what appears to be a Melamine foam piece in a short tube behind the driver, and a large fiber mat in the ear cup. These two larger pieces apear to generally increase the acoustic resistance of the chamber to spoil its Q and reduce resonances.


Removing those two pieces reveals a number of other patches of damping material.

  • Some of the holes on the rear of the driver magnet assembly have been partially blocked.
  • A piece of what might be shelf liner material lines the inside of the earcapsule to break-up its acoustic reflectivity.
  • There are two layers of foam in sections around the circumference of the earcup. These interest me as they have a small amount of space behind them and may act as a compliant damper to reduce acoustic reflections off these inside walls.

There is a very thin, seemingly acoustically transparent, fabric layer that is part of the earpad in front of the driver, but other than that and the protective grill there is no damping in front of the driver. Many headphone enthusiasts have found over the years that while damping behind the driver can be very good, damping in front of the driver can be quite problematic.

It's quite obvious to me that Zach has spent a lot of time working on the damping in these cans. Obvious because of the way it sounds...

ZMF Headphones

thefitz's picture

I'm surprised how home-made these things look when you take them apart. Is this a hallmark of small builders? Does the Ether C look like that once taken apart?

sacredgates's picture

I am dismayed by some of the rather unsubstantial negative comments here. It looks like some folks just enjoy criticizing and I even doubt they actually heard this headphone.

As an Eikon owner I can relate to what Tyll says, but that means also to the many positive qualities he mentions! From my high quality tube amp they definitely make for a very fine listening experience. Yes they are smooth, and the "BBC" dip together with the slightly recessed upper treble make for a more relaxed non-fatigue tuning.
I do find them resolving; it is just not so directly obvious in your face because of Zach´s specific tuning.

Also imho dynamics do not lack with the right amplifier and soundstage is fine; tubes do give a helping hand here. They are closed headphones for sure, and don´t have the airy open presentation of good open headphones.

I consider the Eikon a great addition to the small pack of TOTL closed cans. An in depth and insightful comparison review worth reading can be found on

This review is much more refined than just trashing one headphone and glorifying another. The perfect closed headphone being the best in every aspect for everyone just does not exist. Get to know what qualities are important for you and which tuning suits your taste and equipment (and even that might change with music and mood). Zach has provided us with a very musical and seductive headphone; he never tried to tune them to be be a purely reference neutral tool (and please note that many many other headphones are actually way less neutral than the Eikon). I feel they are one of the most interesting cans at the moment and absolutely worth checking out!

Karalhoin's picture

That's that interesting review that placed the MDR-Z1R in dead last (out of 7 models) in "Overall Performance". A curiosity indeed.

Considering the other 6 models, I had already assumed the reviewer has some exotic preferences (calling people deaf would be rude). It's a very puzzling taste, to say the least. Sadly, it mines the credibility of the rest.

Bobs Your Uncle's picture

From context I believe the intended word is "undermines" rather than "mines".

And to advocate for developing balanced assessments in the manner promoted above by sacredgates:

It's worth remaining mindful that any critical conclusions one may espouse (ostensibly without any undue bias) may be undermined simply by an unfortunate turn of phrase; a result, perhaps, of an incuriously narrow perspective, or indeed through the assertion of unsupported / unsupportable claims. And such espousal will only serve, ultimately, to undermine the credibility of the critical thinker themselves.

Karalhoin's picture

Well spotted. However, we're not all native English speakers in this hobby and to be fair, the thinkers are discussing headphones, not necessarily requiring a perfect mastery of the language. Perhaps like some models can still be a bit amateurish and clumsy made, but we still kinda like their sound and get the message.

Karalhoin's picture

*clumsily, I meant clumsily!

Bobs Your Uncle's picture

No worries, & I fully get the challenges posed by moving between languages; especially when the 2nd language is English. The English language presents some pretty high hurdles to be cleared, but ... at least it's still somewhat more logical & consistent than our politics.

Jazz Casual's picture

The Eikon certainly looks artisanal. Is Sony making any attempt to provide you with an MDR-Z1R for review? I'm most interested in your opinion of it and how it measures up.

Tyll Hertsens's picture
Supposedly....I've contacted them numerous times.
kman1211's picture

Hope you can get a Z1R in for review soon. Do you have any of the new Beyerdynamics coming in for review?

JVG's picture

Thanks for this review, Tyll. Is an Atticus review forthcoming as well?

etrec's picture

I really don't understand your reluctance too review the Audioquest Nightowl Carbon, especially after your fine review of the Eikon. The Nightowl seems to share some of the same traits and type of driver that you describe in the Eikon, but at half the price and at a lower weight.

dynamo's picture

I bought ZMF Eikon this year. And I think this review lacks some important elements of Eikon's sound. First, Eikon's sound is fast, and have good response. Yes, it's warm sounding, but not slow. Lack some detail? I don't think so comparing with my STAX SRM-007tA SR-L700 combo. Reading the review, ZMF Eikon looks like slow and dull one. It is not a fact.