ZMF Atticus Sealed Over-Ear Headphones

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To my eyes, the Atticus is one half of a two part experiment by Zach Mehrbach, Founder and CEO of ZMF Headphones. His past has been dominated by the venerable, but in my opinion underperforming, Fostex T50RP planar magnetic driver. I guess Zach sees his future with a more modern—though more common—dynamic driver. It seems to me he's designed these latest two headphones as an experiment to find out just how good a headphone he can build using two different types of dynamic driver: the Atticus with a TPE (Thermoplastic Elastomer) diaphragm driver; and the Eikon with its bio-cellulose cone and rubber surround.


The Eikon with bio-celulose driver at left, and Atticus TPE driver at right.

With the exception of the driver itself, possibly some minor changes in the damping, and an "A" instead of an "E" on the headband, the Atticus is identical to the Eikon. So rather than redescribe the product I'll point you of to my Eikon review for info on build quality, styling, and comfort...all of which are pretty darn good for a hand made headphone.

The one place worth a good look, however, is inside at the damping. Here's the photos:


There does appear to be minor differences in the materials: damping in the tube behind the driver is pink instead of white. Had a little chat with Zach and he said the bio-celulose driver of the Eikon needs a little less damping than the TPE driver of the Atticus, so the yellow foam of the Eikon is 3lb. foam, and the pink of the Atticus is 5lb. foam. Evidently the various colors of the other parts in the photo do not indicate differing materials.

Sound Quality
Like the Eikon, the Atticus is generally a warm and pleasent headphone that is a bit veiled and uneven in the treble. Bass has a stronger emphasis with a broad hump centered at around 120Hz but does not extend into the sub-bass as well as the Eikon. Looking at the measurements would have me thinking I might hear the bass bleeding into the midrange, but my experience was that the bass was just more emphatic on the Atticus—the mids seem relatively unmolested. Like the Eikon, the presence region is a bit withdrawn, but the Atticus has a much larger dip in response at 6kHz making "ss" sound more "th" than the Eikon.

Going back and forth directly between these two headphones I find it hard to believe the magnitude of difference I hear. It's not that they're terribly different in their tonal character, they're not, it's the overall character of the sound. The Eikon sounds more authoritative; the Atticus more lackluster. The Eikon is more alive and engaging; while the Atticus is a bit dead and boring in comparison. Vocals are more organic and realistic with the Eikon, and rather more artificial and obviously reproduced with the Atticus.

I asked Zach about the differences between bio-celulose and TPE drivers, and how much of this release is about the differences between the two. He answered that it was more accidental than intentional. In his search for a custom specified, high impedance driver he tended to prefer a bio-celulose design, but ended up spending quite a bit of time with the vendor of this particular TPE driver. He does feel that bio-celulose driver probably do have the edge over TPE drivers in terms of sound quality, and though initially he had not planned to build two headphones, he felt this particular TPE driver did some things he liked so he figured he'd build a product around it as well.

He said he does prefer the Eikon to the Atticus, and that most people who get the chance to hear them both side-by-side do as well. But he cautions that both these headphone do respond quite actively to differing amplification, and a number of well respected enthusiasts find the Atticus preferable with high-end tube gear. Having done a little listening comparing the Simaudio Moon NEO 430HA and my Bottlehead Crack I'm going to have to acknowledge the difference is significant with a more fluid and sparkling character.

I had a great time with the ZMF headphones. Most enjoyable was the ability to compare as directly as possible the TPE (Thermoplastic Elastomer) diaphragm driver of the Atticus with the bio-cellulose cone and rubber surround of the Eikon. I've long thought that the micro-fiber diaphragms of the old Sony R10, Sony CD3000, and Denon D5000 had something special. In this comparison the more authoritative character of the bio-celulose cone driver of the Eikon was crystal clear to me.

I'm going to recommend the Eikon over the Atticus, but I'll need to note that the high impedance coils of these headphones make them quite responsive to upstream tube gear. If you're gear is of the electron valve persuasion, I would suggest the Eikon alone, or both if you've got the dosh, for their lively response to high output impedance amps and the great fun one might have with these cans when playing music through that glowing glass. Enjoy!

ZMF Headphones home page and Eikon product page.
Super Best Audio Friends threads here.
Head-Fi reviews and thread.

ZMF Headphones