Abyss Headphones Diana Phi
Headfonics 2019

Abyss Headphones Diana Phi Review

The Abyss Headphones Diana Phi is a stunning compact planar headphone with a flagship-level performance. It is priced at $3995.

Disclaimer: This sample was sent to us for our honest opinion. Headfonics is an independent website with no affiliate links. We thank the teams at Abyss Headphones for giving us this opportunity.

To read more Abyss headphones reviews on Headfonics click here

Please note, that this article follows our current scoring guidelines which you can read here.

Abyss Headphones Diana Phi
Abyss Headphones Diana Phi Review
The Abyss Headphones Diana Phi owns its flagship status with aplomb despite its funky almost cutesy visual aesthetic. It also presents an equally capable but decidedly different presentation to the likes of the Empyrean that make it almost the perfect complement to Meze's masterpiece.
Slide here to add your score on the gear!371 Votes
Reader's Score

Abyss Headphones made their debut on Headfonics in March with the launch of their new Diana Phi luxury line of planar magnetic headphones.

This is not the first time we have been in talks with Joe Skubinski and his team at JPS Labs. We first mulled on an Abyss AB-1266 review as far back as 2013-2014 but at the time stock was like gold dust and rightly so.

We missed the moment but it is not as if we have not heard the AB-1266. Quite a few times actually at various shows in multiple setups.

With the arrival of their new $3995 Diana Phi at the office, we have a few months now under our belt to get beyond our initial impressions and give you the full skinny in a full in-depth review.

Let me tell you this right now. Do not let that portable funkiness deceive you. This is a flagship-class open-back planar performance and easily in the top 3 that I have heard this year thus far.

Technology Inside

So, what is so special about the Diana Phi? Well, to understand this properly you have to go back a bit to the original Diana launch around a year ago. The Diana was conceived as giving you a hefty slice of that AB-1266 performance but in a much smaller package and a slightly lighter hit on the wallet.


But it was not just about reducing the size down from the unique but large AB-1266. The Diana was also about style and having a headphone that simply looked good, like not out of place in a Gucci Store.

The Diana visual was a million miles away from the stuffier and perhaps more macho approach to the headphone design you normally see. It also came in a range of funky colors and matching man-bags. How cute!


But under the hood was no half-assed consumer-level driver. Nope, the Diana was a locally engineered open-back headphone and still had all the setup requirements of a high-end planar such as a resolving amp, good source, and decent recordings. Yup, portable it may have been, inconsequential it most certainly was not.

The Phi Proposition

Roll on 2019 and now we have the Diana Phi. This is pretty much the same shape and style but the driver is now the same as their flagship headphone, the AB-1266 Phi CC.

That is some seriously hardcore planar technology fused into a funky-looking small headphone. Abyss claims the new driver will upgrade the performance over the original Diana and bring it close to their flagship performance as a result.

Abyss Headphones Diana Phi


Honestly, I am blown away by how unique yet sturdy the design is. Just to remind you this is a 350g full circumaural open-back planar headphone with full-sized 63mm phi-planar drivers but it is tiny in every other way. They are not kidding when they call this the “thinnest boutique headphone in the world’.

But size isn’t everything, right? The design is just fabulously retro with square-like cups that have aggressively curved corning and a clever mix of leathers and soft Alcantara finishing stretched over a low-profile gunmetal-toned aluminum frame. There are very few moving parts in this design which I think improves it looks immeasurably.

The plate grills also have this lovely Fibonacci pattern that reminds me of some album covers from the ’70s or acid house era of the early ’90s. I sat on this one during our first impressions feature wondering which album cover exactly and it turns out it was Tool’s Lateralus from 2001 sitting on the edge of my CD stack that most likely jogged that memory.


The material used on the Diana Phi is a blend of practicality and luxury. The one theme I have noted throughout is that none of the materials used are heavy-weight designs, something I think Abyss was very careful to avoid.

The headband slider has a very attractive and super-light carbon fiber finish. The Alcantara is thin, very thin indeed but immaculately stitched.

The aluminum cups are coated with a gunmetal ceramic finish that so far has proved to be quite scratch-resistant. The matching grey-tone leather pads, though small on the outside and not that deep, have a clever but sturdy funnel shape that expands in such a manner to deliver a full circumaural experience. Very smart indeed.

Abyss Headphones Diana Phi

Comfort & Fit

At 330g the Diana Phi is reasonably light for a full-sized planar headphone. Not quite as light as the MrSpeakers Ether 2 but certainly a lot more compact. On the head, my initial impressions are of a good fit but also a noticeable small contact point on the top of my scalp. Something a bit of memory foam might do wonders in terms of pressure displacement.


The Diana Phi headband is quite thin but has only a thin layer of foam so it is a bit more exacting. It is very flexible though so it is not hard to get a suitable fit over the ear. The headband does seem to have just the right amount of length for my head and I consider mine on the small side.


The clamping pressure is spot on for me. Not too much but enough to prevent downward pressure on the top of the ear which is where I always find fit issues to be at their least comfortable with headphones. The leather pads are deceptively big on the inside also so no issues clearing your ear and resting around it properly.

Abyss Headphones Diana Phi

Cable & Connectors


Abyss has opted for 2.5mm mono plugs for the connectors. Now some might feel that 2.5mm plugs are a little on the weak side and that is true when you think of connectors like the flush-mounted Hifiman designs on the older Susvara and HE1000 V2.

However, Abyss has recessed them into the base of the Diana Phi and thrown on some matching wedged barrel 2.5mm jacks on the accompanying cables.

Two things on my initial impressions. The first is the way the unique connectors lock makes for a very low-profile exit point. The second is the wedge when inserted makes for a much stronger connection that is less likely to break.

Abyss Headphones Diana Phi

Stock Cables

You get a choice of stock cables depending on your likely usage scenario. The choice is more termination and length than actual materials because technically the wire is the same no matter what termination you choose.

Termination options included 3.5mm, 2.5mm, quarter-inch jack, 4.4mm, and XLR 4-pin on the jack side. For length, you can opt for the stock 1.5m if you are planning on moving around and then 0.5m incremental increases to 3m for home use. There is a $50 additional fee on the checkout price for every 0.5m you add to the cable.

Before Abyss there was JPS Labs, which, if you do not know, was and is a cable manufacturer. That is a plus for the supplied stock cables with the Diana Phi because they are finished to a very high standard indeed.

For this review, we received the 3.5mm with a quarter-inch jack converter and the XLR 4-pin, both in 1.5m formats.

Abyss Headphones Diana Phi

Cable Finishing

The finishing on the stock cable is a thick but pliable rubber jacket sheath over a 24AWG custom copper alloy conductor which then splits into 2-wire per channel beyond the metal Y-split using a transparent thinner jacket.

The 2.5mm barrels are uniquely shaped to fit into the base socket of the Diana Phi so they can recess nicely. It does not mean the sockets are proprietary but they are quite narrow so thin 2.5mm dual-entry alternatives will work such as the Hifiman Single crystalline stock but nothing wider.

Though it matters less on open-back headphones, the stock cable is 100% microphonic-free even above the Y-split. There is also an easy cable to work with having no memory retention or none of that annoying stiffness or flyaway quality you find on other stock headphone cables.

Abyss Headphones Diana Phi

Accessories & Packaging

I am digging everything I am seeing regarding the visual and physical vibe Abyss is giving out with the Diana Phi packaging. For some reason, in this hobby, we are obsessed with black or dark packaging with black-painted or woody headphones. The odd time we get white such as Oppo PM-3 but rarely at the top-end.

The Diana Phi package is nothing like you would expect and it continues right down to the headphones themselves. This was an unboxing full of “Wow I did not expect that”.

First, the box is not that big but not surprising given the Diana Phi is not a hefty headphone. It is the graphical design and use of white that I like most about it. It feels fresh, and on the side, it looks almost like it was inspired a little by the Houston Astro’s famed 70’s outfit for those who remember it.

Abyss Headphones Diana Phi


Inside that Astro’s vibe continues with a gloriously retro carry bag (it is a man bag) which houses the Diana Phi. This double zipper soft nylon and leather finished carry case is the bomb I kid you not. I love its look and it fits perfectly with the whole Diana Phi styling vibe to a tee.

Inside you will find your cable, the type of which will depend on what you picked at the checkout on their website.

This one includes a 1.5m 3.5mm terminated cable with a 6.35mm adaptor as well as a similar length 1.5m cable with a 4-pin XLR termination. You can also opt for 2m, 2.5m, and 3m lengths as well as 2.5mm and 4.4mm terminations when buying the Diana Phi.

Click on Page 2 below for Sound Impressions & Synergy

Sharing is caring!