We review the HEDD Audio HEDDphone Two, which is a 2nd generation set of open-back headphones using AMT or Air Motion Transformer drivers. It is priced at $1,999 or €1,999 in Europe.
Disclaimer: This is a sample that was sent to us in exchange for our honest opinion. Headfonics is an independent website with no affiliate links. Many thanks to HEDD Audio for their support
You can read about previous HEDD Audio products we have previously featured on Headfonics here.
Note, that this article follows our latest scoring guidelines which you can read up on here.
The HEDD Audio HEDDphone Two still creates a very different and cool proposition to what is currently out there in the headphone market.
However, the looks have radically changed as also the sound compared to the original. This is a flatter more muscular sound signature with a heavier emphasis on midrange excellence. It works a charm with metal and thrash and anyone looking to get up and close to guitars in their audio listening.
It is almost exactly 3 years since HEDD Audio launched the original HEDDphone. This was one of the more unusual headphone releases in 2020 because of the use of a full-range AMT driver at what some might perceive as competitive price for a flagship headphone.
My take was that it sounded pretty good but like almost everyone else, that 718g weight presented quite a challenge for comfortable long-term listening.
So, here we are in 2024 with a review of the HEDDphone Two, the 2nd generation version of this ambitious path for the company. It looks different, very different. It also sounds quite different from the original, but most importantly for many, it weighs a lot less.
Tech Highlights
On a high level, the HEDD Audio HEDDphone Two retains the same basic principle as the first-generation version. This is a circumaural or full-sized open-back headphone that uses a full-range Air Motion Transformer driver or AMT for short.
The AMT driver consists of a folded Kapton diaphragm, (Kapton polyimide film), which, on paper seems similar to the original but in fact, it’s a completely new driver engineered from the ground up.
The HEDDphone Two has a 41Ω impedance rating with a fairly demanding sensitivity level of 89 dB /mW but slightly improves on the 42Ω and 87dB SPL benchmark of the original HEDDphone.
However, you are still going to need an amplifier that can deliver quality power to provide the headphones with enough headroom to perform optimally. I found the likes of the Ferrum OOR and HIFIMAN’s Prelude to be more than sufficient and were the two primary amplifiers used for this review.
AMT & VVT Technology
For those who are new to HEDDphone Two’s AMT technology, this is a very different driver design from planar or dynamic. Perhaps the closest is a ribbon array but even then the folded accordion-like articulation means it sits out there as something quite different to the more familiar driver mainstays.
AMT is an electroacoustic transducer, unlike traditional planar ribbon designs. In contrast to a planar ribbon, the diaphragm of an AMT is of a pleated shape similar to a bellows design.
Unlike conventional diaphragms, the AMT diaphragm in the HEDDphone TWO is made of Kapton polyimide film, bonded with conductive aluminum strips.
The diaphragm is then suspended within a multi-directional homogenous dipole-driven magnetic field creating a very tight and tense pressure environment when a signal is passed through the folded pleats. That means it moves air a heck of a lot faster than conventional diaphragms, up to 5 times faster.
They are designed in such a way to have a much lower mass than conventional diaphragms. And because the diaphragm is folded, the active/driving diaphragm surface area is much larger than that of a conventional diaphragm.
With this increased surface area the AMT needs only much smaller excursions to get the same air volume displacement, (or sound pressure), as conventional flat surface diaphragms.
For many, AMT is seen as essentially a tweeter driver with a more limited range. To ensure the HEDDphone Two’s full-range driver delivers a linear response across the full FR, HEDD Audio uses proprietary Variable Velocity Transformation, or VVT technology for short.
This is essentially a variable diaphragm geometry, rather than fixed in structure with variations in both the width and depth of the folds.
Design
The HEDDphone Two design is a massive change from the first version, particularly in terms of weight and their respective form factors.
It is both lighter, and slimmer but also significantly taller courtesy of the introduction of the company’s new HEDDband. Yes, it is spelled correctly and it is rather complex. However, it’s one of the few headbands I have worked with down through the years that can alter both the clamp and fitting at the same time.
I would also argue that HEDDphone Two is much closer to the company’s core design language and color scheme used for its established HEDD MK2 speaker range with that muscular grill framing combined with a matt black finish.
So how did HEDD Audio get the new version lighter? Quite a few things it seems. Gone is the traditional spring steel and memory phone wrap of the first version and instead we have a carbon fiber arch combined with a mix of protein leather and foam for the new HEDDband strap. That’s a few grams gone there at least.
We also have smaller cups with reduced enclosure depth, improved swivel, and similarly reduced sizing for the accompanying detachable perforated protein leather ear pads. This in turn allows HEDD to introduce yokes that are half the size or length of the originals so’ bye-bye’ more weight.
The final significant change that might well be a factor in its weight reduction is the switch from larger mini-XLR connectors to slimline 3.5mm TRS angled ports molded into the base of the HEDDphone Two cups.
Comfort
At 550g compared to 711g the HEDDphone Two is lighter and immediately more comfortable to wear compared to the original version.
It is still within the realms of heavy being around the same weight as something like the ZMF Headphones Caldera or the LCD-2 Classic headphones from Audeze.
However, all credit to HEDD Audio for getting it down to more reasonable limits with their new lighter carbon fiber band and the HEDDband system which is made of ribbed memory foam and a breathable fabric outer.
It is not immediately intuitive how to use it but once you understand it’s pure genius. This is much more useable than the older V1 classic single-band strap giving you a very wide range of fitting styles for the HEDDphone Two.
Initially, when I tested the fitting the sizing felt a bit too big for my head. Even with some cursory adjustment of one of the leather HEDDband straps it didn’t make a huge difference until I studied it a bit more and realized there are two ‘layers’ of straps, upper and lower.
The lower shape strap adjusts the overall position or height of the HEDDphone Two strap to align the cups and pads properly with your ears. The upper tension strap is all about clamping and this is the one I wanted to get right because the pressure distribution can have a big influence on long listening comfort.
Now admittedly, I had a few attempts to get the right blend of pressure and position but I got there in the end. Once set, I doubt I will go back to it much unless I want to loosen it up a bit for longer listening sessions.
Stock Cable(s)
As if we are not done with ‘downsizing’ and weight reduction on the HEDDphone Two itself, we also now have a much lighter and more refined cable system.
I call it a system because you get two cables with 4 connector options with HEDDphone Two compared to just one size fits all with the original.
Each cable is terminated with either a 4.4mm balanced Pentaconn jack or a single-ended 6.35mm plug with additional piggy-tail connectors to ‘upsize’ to 4-pin XLR or go small with a 3.5mm TRS.
Both cables are also much lighter and more malleable than the cloth-jacketed stiffer original version. They are beautifully braided with a low-profile aluminum splitter barrel and matching termination barrels, all in matte black.
The piggy-tail converters have a similar finish save for a knurled gold ring on the end that I found could be loosened quite easily. Not sure it was designed to be that way but just keep an eye on them to make sure they do not come loose.
The wire geometry itself is an 8-wire design using Kevlar-infused braided 12 x 4 OFC copper. Each braided strand has an O.D. of 0.90mm.
Packaging & Accessories
Like the original, the HEDDphone Two comes in a big bulky box. You certainly will not feel short-changed with how everything is packaged inside.
Just about everything I mentioned that needed to be worked on for packaging and accessories in V1 seems to have been remedied with the new version. That means a carry case, a big one and one that is nicely formed to hold just about everything safely inside, including cables and even the spare pads if you position them just right.
So what do you get aside from the carry case? Well, there are the cables and connectors, a set of spare pads which is always welcome in our remote location, and some additional pamphlets with QR codes.
Do not throw those away. Use the QR code on one of them and get your 5-year warranty which is one of the longest warranty periods for any headphones that I know of aside from Koss’s lifetime warranty.
I do have to pay special attention to the presentation of the HEDDphone Two’s accessories.
They have their own special box and are all very beautifully laid out in a protective tray for you to get an instant idea of what is available to you.
It sort of reminds me of a well-laid-out IEM package and one which headphone companies should pay attention to. A few I think can come close would include T+A’s Solitaire P and P-SE‘s grandiose layout but they also cost a lot more. Interestingly, both companies are German.
Click on page 2 below for our sound impressions and recommended pairings.
