DUNU VULKAN

Dunu Vulkan ($379): What’s in a name?


Vulkan


Upon reentering the portable market in earnest, the Dunu Titan 1 was my first purchase. For the price, it sounded quite good. Then Dunu seemed to fall a bit behind other far eastern manufacturers, or so it seemed. With the SA-6, Dunu reentered with vigor. Multiple changeable jacks were included, so all one needed to do was change the jack, not the whole cable. It worked, and we consider the SA-6 as one of the top contenders at the $500 IEM price. It also seemed that Dunu took a step away from the traditional far east sound of a nice bright signature, which carried over into plenty of air between notes. While not a bad signature, it really was not for everyone. That type of signature works wonders for classical or opera music in our opinion, but not so well with other genres.


Celebrating their 20th anniversary soon, Dunu started this road with the models mentioned earlier. Moving upscale, the DN-1000 coaxial hybrid IEM of roughly 10 years ago claimed to be the first hybrid IEM under $1000. While we mentioned that it seemed they had taken a step back and were not heard from for some time, they were working diligently on introducing their new technology into a budget-friendly price. The Vulkan is the latest evolution of their coaxial designs, using their expertise in design and tuning. Priced just under $400, it sits in the middle of their range, between Falcon Pro and EST112 (part of this information was taken from the follow excellent review: https://www.ear-fidelity.com/dunu-vulkan/)


The Vulkan follows this “new” Dunu sound/research with much going for it, including the changeable jack. With gorgeous looks, excellent build and the jacks going for it, there is much to like. Read on for more positive vibes.



Specs:

MODEL: DK-X6 (VULKAN)

NET WEIGHT: 17 g
FREQUENCY RESPONSE: 5 Hz – 40 kHz
IMPEDANCE: 15 Ω at 1 kHz
SENSITIVITY: 109 ± 1 dB at 1 kHz
TOTAL HARMONIC DISTORTION: < 0.3% at 1 kHz

DRIVER UNITS

DYNAMIC DRIVER UNITS [2]:
8 mm Cross-Linked Polyethylene Structural Foam Cell Dome with Soft Independent Surround [1]
8 mm Nanocrystalline Titanium-Coated Diaphragm [1]

BALANCED ARMATURE UNITS [4]:
Knowles Mid-High Driver (×2) [2]
Knowles Dual Supertweeter (×1) [2]

CABLE SPECIFICATIONS

WIRE MATERIAL: 4 Core, High-Purity, Silver-Plated OCC Copper Type 1 Litz (DUW-02S)
LENGTH: 1.2 ± 0.1 m
CABLE CONNECTOR: Patented Catch-Hold MMCX Connector
PLUG CONNECTOR: Patented Q-Lock PLUS Quick-Switch Modular Plug System

INCLUDED PLUG TERMINATIONS:
3.5 mm TRS Single-Ended
2.5 mm TRRS Balanced
4.4 mm TRRRS Balanced

Gear used:

Astell & Kern ACRO CA1000




Songs

Mostly jazz
Female vocals


The Beginning:

Packaging has always been a strong point for Dunu models, and when one spends this kind of money, the presentation melds well at this price. Much useful information is also printed on the box from specifications, to driver type and size; as well as information regarding the cable and accessories included. The cable itself is called the DUW-02S, with the Q-LOCK PLUS system for changing jacks. It’s a four-core, silver-plated OCC copper of type 1 Litz design. MMCX connectivity is used for additional support. The cable lays nicely and is of a softer variety, aiding in no microphonics.

The faceplates are inspired by the Japanese art of Mokume Gane, a 17th-century technology producing complex metal laminates in separate layers. The name translates to “wood grain steel”. This laminate was then used to produce swords and knives like katana, wakizashi, and tanto. You can somewhat feel the separate “layers” on the dark gray/black faceplate and under the right light, is stunning in presentation. A slot on the forward side acts as a vent, completing the look.


The same dark gray/black carries over into the moderately sized shells complete with “Vulkan” and either “L” or “R” on the inside. Thankfully, no fancy ear nubs are found on the inside, affording good insertion depth, even with the wider than “normal” nozzle. A silver screen covers the large nozzle as well. With a shrink wrap sleeve over the business end of the cable, there is a good over ear guide, leading to the understated stunning shell.

The Q-Lock Plus changeable jack system allows the user to utilize three jacks on one cable, alleviating the need for multiple cables. The wizardry inside switches to balanced or single-ended depending upon the connection, whether it be 3.5mm for single ended (TRS), or 2.5 (TRRS) & 4.4 (TRRRS) in balanced mode. One might worry about the complexity or failure rate, but you should not. Built to withstand several hundred to thousands of changes, the jacks hold up very well.



Technology:

The Vulkan utilizes six drivers per shell: four Knowles balanced armatures (2 mid-high & 2 super tweeter) along with one 8 mm Cross-Linked Polyethylene Structural Foam Cell Dome with Soft Independent Surround and one 8 mm Nanocrystalline Titanium-Coated Diaphragm (a co-ax dual dynamic driver). That vent slot (Air Control Impedance System, ACIS) on the faceplate helps alleviate pressure build up, as well as control the bass segments; giving more control over the lower end. Dunu does their testing inhouse, along with design and build so they can control all points except for the actual building of the drivers. This helps to control sound quality from build point to finished product as well.



Sound:

The SA-6 is one of our favorite IEM’s at the $500 price point. Many will be satiated with it to the point of stopping their search. The Vulkan may have the same effect, but at a lower price. With excellent upper reach control, and the dual dynamic drivers caring for the lower, the Vulkan proves its mettle across the sound spectrum.

The bass while not as impactful as some other dual dynamic drivers still holds its place with excellent control of the lower spectrum. Taut and controlled, I do wish for a little longer decay so those tendencies would linger. To me this would give more girth to the bass while not meddling too much into the mids. Nonetheless, the bass can show itself nicely such as on Taylor Swift’s new song Snow On The Beach. From her absolutely highly acclaimed Midnights album, the song enters with a solid bass line, and there is a bit of reverb through the Vulkan. The same holds true on You’re On Your Own, Kid, which makes me believe it is on purpose. Giving excellent tight control here makes that reverb all the more refreshing. Tip choice is paramount to good quality bass, and the Vulkan benefitted from one of my trusty Comply foam tips. Bass became very, very good as a result.

One need not say much about Swift’s vocals. They are divine. And through the Vulkan, there is a certain sumptuousness to it, which makes the musical notes completely believable. Often with multiple balanced armature drivers, there is a tendency to “overproduce” the upper mids leading into the high notes. Thankfully here, there is a certain trueness to her vocals, with no underlying analytical sounds either from the extremes of her vocals or the background instruments. With more drivers, you can run into a “business” of sound, which translates into that analytical sound of which I speak. Not here as her steamy voice comes through with complete realism.



Moving into the upper regions, cymbal clashes, even those made by digital representatives sound realistic as well. There is excellent reach of note, giving very good air to the notes, but not translating to a thinness often accompanied by extension in the treble region. This translates into good weight to the notes across the spectrum as well. Often when treble sounds brittle, or glitzy, it dissuades from the overall signature, making it seem thinner or more brittle. Not here though. The treble gives extension where needed, and spreads the notes out in an even manner, complimenting the taut and controlled bass. The benefit of this? The mids. Female vocals are made for the Vulkan. Trust me.

While the parts listed above give an excellent sound signature, I did find that the reach from the top makes for a bit tedious sound on some songs. Especially those with a preponderance of upper, such as EDM. Sound stage is still excellent in the three dimensions, giving very good placement to the instruments and layering. Height to me dominates the 3D cube, but not to the detriment of width or depth. In fact, that expansion may give a false sense of expansion, with the depth showing through with excellent character on certain songs. Width is beyond my ears, making its resolve to give that 3D shape good shape.


Conclusion:

We are fans of Dunu, counting some of their models as the best or near best in their respective price categories. We wholeheartedly recommend the SA-6 to many who have that money to spend, because with each jack change; you can tailor the signature a bit to fit your music. Dunu in its 20 years has taken that experience of “tinkering” to settle on a fairly unique structure with the changeable jacks, as well as providing an excellent sound foundation to back it up. While not perfect, the Vulkan shows it can certainly fit into the market as Dunu’s low-cost hybrid IEM. We hope that Dunu keeps innovating, going their own way to produce what they think is the best that they can provide. If the models mentioned here are the result, Dunu has followed their heritage line of hybrid driver IEM’s with exemplary fashion. We can highly recommend a listen if you are looking for a fun, engaging sound signature in your next IEM.

DUNU VULKAN & DUNU DTC-500

Dunu Vulkan is sent to me as part of Dunu Vulkan Malaysia tour,
I have received the Dunu Vulkan alongside Dunu DTC500,
my impression will be solely based and tested with pairing Vulkan to the DTC500 on both PC and Smartphone as a packaged sound.


THE BUILD

Dunu Vulkan is constructed from a solid aluminum for its body and with a very beautiful damascus inspired faceplate,
it features mmcx ports and the cable it came with have swappable plugs.

Dunu DTC-500 is a solidly machined aluminium with angular shape that reminds me of the infamous Tesla Cybertruck,
it features coloured lights that indicate decoding sampling rate and a USB C port.



THE SOUND
Introduction of Vulkan voicing.
Vulkan is one would call a standard V-shape fun sounding IEM, bombastic bass and shimmery highs gets the feet tapping as I listening to the tunes.
Technicality wise, to my ears it is not the best in class but it certainly is in the ball park for a Mid-Fi level in detail retrieval and presentation.

BASS
What comes to my surprise at the moment I first listen to Vulkan is how visceral the bass is, strong and impactful.
But what is a big wow at first slowly fades into a mild annoyance for me as the bass quantity is too much from how I usually like it.
The low end rumble still retains some level of authority but it does fall short and landed in the bloated category,
on some electronic music the elevated bass is a welcome sound,
but for most orchestral music it does not present itself natural enough to accommodate the nuances those music asked for.

MIDS
The mids is a full and forward presentation, for me vocals presence is being a light exaggerated and brought forward in a energetic sense.
I especially like the male vocal on the Vulkan, the deep grunt it able to present on deep male voice sounded quite enjoyable.
Female vocal instead it have less focus on mid high which can cause some weird texture for me,
there is some degree of glare and sibilance which I have clearly noted from the choices of songs I have tested with.

TREBLE
The treble are energetic and airy, a very shimmery presentation, at times have some slight glaring hot treble but at most time are still well controlled.
Some hotly mastered Japanese pop song I have listened to can get messy with too much treble glare that outshines most of the track, but that is only limited to some very messy passages in the song.
Violin sounded quite exquisite, having the strings pull recreated with high energetic and lively sound, it was a very pleasing experience.

STAGING
The Vulkan is not an IEM that accel in large staging, rather I will describe it as a bubble around the head, it have adequate amount of sound field to not feel congested but not large enough to perceive an out of head experience.
In all way a decent staging but not an amazing one.

FINAL WORDS
The Vulkan is priced at 380USD while the DTC500 is 90USD, as a package, they compliment each other as a porta-fi on a budget package, one make sure the other is fed with ample power while the other delivers in optimal condition.
As a sub 500USD package they are highly competent against quite a handful of competitor's IEMs, but to my ears,
there are still much room for improvement and I will continually look forward for Dunu upcoming releases in hoping they pursue further in the never-ending journey chase for the sonic perfection.

Tonality: 6/9
Technicalities: 6.66/9
Preference: 6/9
Total: 6.2/9 (B)
(star rating is for the price to performance)


(total 5 mins read)
Intro
Dunu is one of those matured Chifi companies who have made numerous statements with their releases like Luna & Zen (though I haven’t listened to them) and the ever-popular SA6. I believe they have their own niche in the market and always looking brilliant and metallically-solid with every release even with their entry-level IEM called Titan. I’m not going to pretend that I know Dunu that much, just like most people do, I read.

Vulkan is a new hybrid offering from Dunu for the mid-fi market that competes with the likes of Tanchjim Oxygen, Yanyin Canon, Unique Melody UM 3DT, and Moondrop Blessing 2 just to name a few. It sports an 8mm coaxial dual dynamic driver for the bass, 2 Knowles balanced armatures for the midrange, and 2 Knowles balanced armatures for the high response. The housing is CNC-machined aluminum that feels very solid as usual that comes with a nice Mokume Gane-inspired faceplate. Overall, I’m loving what I’m seeing here. But the question is, how good is Vulkan sonically?


Signature
The sound signature of Vulkan can be described as neutral with a bass boost that skewed towards a darker & warmer tonality that’s pretty balanced in my opinion. Some might call it mild V-shaped or U-shaped depending on one’s sensitiveness towards treble and bass response.

The treble here is done tastefully, which is not the common "in-your-face" kind of treble for perceived detail we mostly find these days. The bass glides smoothly from the lowest octave to the mid-bass before its relatively relaxed midrange. It’s like a colored neutral tuning but in a good way. Overall, I think the tuning is pretty solid and enjoyable if not as refined as other competitors within the same price bracket.



measurement graph courtesy of precog.squig.link


Tonality
Tonally, I find there’s nothing wrong with Vulkan but perhaps lacking in certain areas like the upper midrange and upper treble response for a more "natural" playback other than its marginally dry timbre (more on this later). Although I’d love to have a smoother and airier treble with a more forward upper midrange presentation, I kind of dig what Dunu did here with the Vulkan.

One of the good things is the transition between midrange and treble is fluid and coherent like a full-range dynamic driver. The midrange is not the cleanest but rather dense with a good note-weight and warmth. But there’s something bothering me at times. It could be the peak around the presence area or the lack of upper midrange response that somewhat makes the treble appear “compressed” at a higher loudness listening level or when there’s overlapping of treble information. There’s no detrimental sibilance whatsoever, but there’s lower treble harshness or excessive lower treble energy for sure. The issue varies with different sources which evident that Vulkan has a good range of scalability.

While the bass is not a true "bass-head" level, it’s satisfying enough in terms of amount and quality and perhaps the best trait of Vulkan. Mid-bass is punchy and articulate while the sub-bass digs deep enough with good rumble while not being too forward or overpowering. It has decent texturing with a natural decaying ability that also helps to give a bit of “life” to the overall playback. In my opinion, it’s not the best but also not the worst bass at the same time. Overall, I can say that Vulkan is tonally balanced and musical at most.


Technicalities +
Vulkan boasts good resolution which presents a relatively wide than tall sound stage that I find quite impressive. However, it’s not the most resolving regardless of the big image it reproduces. The transient attack is fast yet the note comes off a little dull in terms of solidity (density). Thus, the imaging is good and unique in a way but sort of hazy or not as crisp or sharp. This is to say that Vulkan has an average clarity in the grand scheme of things which is absolutely not a bad thing, but just middling in hammering out micro details.

In other words, Vulkan has a kind of big “out-of-head" image projection yet it’s not as clean or detailed to be able to see the overall picture. What I like about Vulkan’s presentation is the sounds feel almost tangible. It feels like the imaging is holographic with a good sense of space & separation between instruments.

Regarding the timbre, I honestly think it’s not the worst kind of BA timbre I’ve heard. It appears to me that this timbre is what makes its "big sound". It requires some time to adjust to this kind of big sound especially those coming from a neutral or reference-style tuning. Imagine every note is enlarged, so, the smooth treble you’re accustomed to now appears in a more lifelike manner rather than the typical miniature sound coming out from your typical earphones (it almost feels like listening to a pair of desktop speakers).

Speaking about dynamics, I’m going to say that Vulkan is doing just fine. To be frank, it’s great with the lower part of the frequency spectrum but a little bit compressed around the top. For example, Vulkan shows great slams & impacts on Zu’s “Carbon” from start to finish but comes off as slightly flat or moderate for brass instrument attacks on Sinne Eeg’s “We’ve Just Begun” at around 0:40-1:42 minute mark. Generally, to me, it’s simply adequate and serviceable in terms of dynamics.









Comparison
I believe Moondrop Blessing 2 is the most compared IEM if not the only true challenger to Vulkan. Both of these IEMs have a similar configuration and are priced within the same realm of competitiveness (Vulkan with dual dynamic driver and an additional $60 premium).

Blessing 2 is by far regarded as the standard or benchmark for IEMs below $500 by many enthusiasts in terms of tuning-wise and resolution-wise. Some might even say it’s the best within the kilo buck range if not the best in value. Coming from Blessing 2 or neutral camp generally, I find myself leaning towards Blessing 2 most of the time. However, after some time, I can vouch for Vulkan to be an equal or a rival to Blessing 2 for different reasons.

While Blessing 2 is a true studio monitor with an analytical or reference-style tuning approach, Vulkan is a more natural and musical set. Other than near-top resolution & a cleaner presentation, Blessing 2 boasts better micro dynamics too. Vulkan on the other hand boasts an atmospheric presentation that is a wide sound stage and a bigger image with explosive impacts. Musical instruments sound more realistic on Vulkan whereas Blessing 2 is more detailed. So, it’s totally depending on what one wants in their music playback fix. I find myself liking both of them for their own strong qualities.


Valuation
As much as I like to listen to my classical music collection with the Blessing 2, I find Vulkan to be slightly more enjoyable, more pleasant, more satisfying, and more delightful overall (you get what I mean). This is not to say that it’s only good for classical but also with most of the music tested (mainly acoustic and live recordings). I can say that I realized a different perspective once I started digesting the tuning, especially the treble (please check out my test track ratings with the Vulkan below).

For those looking for top-level resolution or absolute clarity within the price, Blessing 2 might be the answer. While Vulkan is not perfect, it’s honestly very good for what it is. I think I’ve never heard anything like it since into the hobby (particularly IEM). It’s simply unique and fun. Without talking more nonsense, I’m going to recommend Dunu DX-F6 the “Vulkan” for its "true to musicality" nature while retaining a solid degree of Dunu's own elegance. Good job Dunu.


-----------------------------------------------------------------------------------------------------------------------------------------------------------
*this unit is sent by DUNU for the Malaysia tour in exchange for an honest review. all words are 100% mine and I'm not compensated or influenced by any party.


Purchase Dunu DX-F6 Vulkan here (non-affiliated)

tools:
Tidal / Apple Music via LG G7 / Macbook Pro with/without Ovidius B1 / Hidizs S9 Pro / Dunu DTC 500
Tidal / Foobar2000 (FLAC) via Topping EX5 with/without Aune X7s or Aune S7 Pro

key songs & ratings: (technical & enjoyment)
Será Una Noche – Taquito Militar (Tango) 5/5
Eddie Daniels – Baião Malandro (Jazz Fusion / Classical Crossover) 5/5
Patricia Petibon - Mozart: Der Zauberflöte – Der Hölle Rache kocht in meinem Herzen (Classical [Aria]) 5/5

Sinne Eeg – We've Just Begun (Jazz) 4/5
Cécile McLorin Salvant - Ghost Song (Vocal Jazz) 5/5
Ryan Gosling & Emma Stone - A Lovely Night (Jazz Pop / Film Score) 4/5

Muddy Waters – My Home Is in The Delta (Delta Blues) 4/5
Stevie Ray Vaughan and Double Trouble – Tin Pan Alley (Blues Rock) 5/5
Nick Cave & The Bad Seeds – Red Right Hand (Alternative Rock / Punk Blues) 4/5

toe - 孤独の発明 (Math Rock) 4/5
Tera Melos - 40 Rods to the Hog's Head (Math Rock / Avant-Prog) 3/5
Don Caballero - Don Caballero 3 (Math Rock) 3/5

Scott Walker – Corps De Blah (Experimental / Post-Industrial) 5/5
Swans – Lunacy (Experimental Rock / Post-Rock) 5/5
Zu - Carbon (Avant-Garde Metal / Avant-Garde Jazz) 5/5

My Disco – A Christ Pendant Comfort Her Neck (Noise Rock / Post-Hardcore) 4/5
Arab On Radar - God is Dad (No Wave / Noise Rock) 5/5
Shellac - Crow (Post-Hardcore / Noise Rock) 4/5

Mastodon – The Wolf Is Loose (Progressive Metal / Sludge Metal) 4/5
Fear Before the March of Flames – High as a Horse (Post-Hardcore / Metalcore) 3/5
Botch - Japam (Matchcore / Post-Hardcore) 4/5

ANOHNI - Drone Bomb Me (Art Pop / Elctropop) 4/5
Slowdive - Star Roving (Shoegaze / Dream Pop) 4/5
The Shins - Simple Song (Indie Pop / Psychedelic Pop) 4/5

Radiohead - Idioteque (Art Rock / Experimental Rock / Electronic) 3/5
TheFatRat - Warbringer feat. Lindsey Stirling (Electropop) 4/5
Massive Attack - Unfinished Sympathy (Trip Hop / UK Hip Hop) 4/5

Justin Bieber - Holy feat. Chance the Rapper (Contemporary R&B / Dance-Pop) 4/5
Lizzo - About Damn Time (Contemporary R&B / Dance-Pop) 5/5
Kylie Minogue - Real Groove (Dance-Pop / Nu-Disco) 4/5

Click to expand...