DUNU is one of the most esteemed brands in the IEM world, having delivered heavy hitters like the the Zen Pro and Titan S. Its latest release may just be its most exciting: the Vulkan. Volcano-inspired and exceptionally stylish, this new set features a hybrid design composed of two dynamic drivers and four balanced armatures per side. It’s not just about driver count either, as it includes DUNU’s latest acoustic technologies to deliver a unique sound to keep you coming back for “just one more song.”
Do these high aspirations succeed? Find out in our review!
- Current Price: $379.99 (Amazon)
- Model: DK-X6 (VULKAN)
- 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
- Dynamic Driver Units :
- 8 mm Cross-Linked Polyethylene Structural Foam Cell Dome with Soft Independent Surround 
- 8 mm Nanocrystalline Titanium-Coated Diaphragm 
- Balanced Armature Units :
- Knowles Mid-High Driver (×2) 
- Knowles Dual Supertweeter (×1) 
- 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
- Net Weight: 17g
DUNU Vulkan - First Impressions and Key Features
The DUNU Vulkan are unique earphones in more ways than one. They use a hybrid design composed of dynamic drivers and balanced armatures, but what makes the Vulkan special is how that arrangement comes together.
Inside of its gorgeous lava-themed shells, the Vulkan utilize two dynamic drivers (one 8mm foam cell driver and another nanocrystalline titanium coated driver) alongside four high-quality Knowles balanced armatures. That’s remarkable as the vast majority of IEMs available today utilize a single dynamic driver. The two dynamic drivers cover the bass and some of the middle-frequency ranges. One pair of BAs cover the middle-highs and the other two act as super-tweeters covering the highs.
The question is, why. Over this last year, we’ve seen a resurgence of single dynamic driver IEMs that can sound quite good, so why pay extra for a multi-driver hybrid like this?
First off, it’s important to understand what’s happening between those drivers. The entire frequency range (think of it like a line) gets split between those six drivers using a small electronic component called a crossover. Those drivers are only firing for their particular frequencies, sometimes more and sometimes less. Mixing those driver types lends the Vulkan (and other hybrid IEMs) a unique sound and timbre and gives the engineers at DUNU more latitude to fine-tune the exact signature they’re looking for. At the same time, it also ensures that no driver will ever be pushed to its limit, so distortion should never be a problem that you’re hearing.
This driver arrangement allows for a wide frequency response of 5Hz to 40kHz, tuned to a gentle U-shape. It has an impedance of 15 ohms and a sensitivity rating of 109dB, so they’re very easy to run, even off of a dongle DAC. I was pleased to find that they scaled well with additional power, improving in bass response in particular.
There are plenty of multi-driver IEMs that cost less than the Vulkan, however, so clearly the appeal here is more than just the drivers. The tuning is certainly a part of it, and an element that DUNU has shown itself to be a master at. It’s also about the supporting technologies. Surrounding the dynamic drivers and the super-tweeters is a 3D printed acoustic waveguide to reduce interference between the sound waves. DUNU has also implemented its latest Air Control Impedance System (ACIS) to bolster low frequency support and vent from small grilles in the faceplate.
There’s also craftsmanship and long-term durability. The earphones are made of CNC-milled aluminum for increased durability. The faceplates are modeled after the layered pattern of igneous rock and may well be considered artisanal.
It’s also about what else DUNU includes in the box, starting with the cable. In this case, we have a beautiful cable made of 4-core, silver-plated OCC copper, litz braided, color matched to the silver, gray of the monitors. It’s soft and supple, and doesn’t transfer microphonics up to the ear. It also features modular terminations. Using a retractable sleeve, the plug can be removed and swapped out in seconds. There are 2.5mm balanced, 3.5mm single-ended, and 4.4mm balanced connections included, as well as a 3.5mm to 6.35mm adapter included.
DUNU also includes a selection of silicone tips in different sizes and bore widths, and an excellent travel case. The case is the real star of the show and feels much higher quality than the usual boxes we find from the competition. Kudos to DUNU for continually delivering such a full package to consumers.
DUNU Vulkan - Fit and Comfort
The Vulkan are what I would consider a larger IEM, which may cause fit issues for users with smaller ears. I’m fairly average in that department and was able to find a comfortable fit with my usual medium-in-the-right, small-in-the-left configuration. They use a traditional shape for an IEM and long enough nozzles where they’re secured by both the ear canal and your outer ear. With the proper tips, I didn’t have any soreness or fatigue, even after multi-hour listening sessions.
DUNU Vulkan - Listening Impressions
Testing for this review was conducted using a mix of my Fiio M11 Plus ESS DAC using lossless files and Spotify on Very High Quality. I used the white tips and sources music from mainstream pop, to metal, to classical. I also played multiple games on my PC, using the Fiio BTR7 as an external soundcard. The overall tuning is very mainstream friendly, with plenty of bass and detail throughout the mids and highs.
Bass: Excellent sub-bass extension is the hallmark of these monitors. DUNU has tuned them with elevated sub-bass which lends music tactility and substantial body. I’ve been trying to add a bit more orchestral music into my testing routine, and I was happy to have done so with these IEMS. The Vulkans gave the cellos on Reminiscence by Olafur Arnalds and Alice Sara Ott a wonderful fullness that complimented the melancholy violin singing on top. Returning to mainstream pop, D.R.E.A.M. by Jonny Craig lives and dies on sub-bass, and the Vulkan nailed the first drop and gave sufficient rumble throughout the rest of the song. There’s plenty of texture, detail, and speed present here. You would expect a set with two dynamic drivers to have solid bass performance and it definitely does.
Mids: Because the bass stays in its lane with this set, I didn’t find that it bled into the mids to add unnatural warmth. The mid-range tuning definitely pushes vocals to the front of the mix. Singers cut through, but sound natural and airy. Mid-range instruments have plenty of detail that is easily discerned due to the excellent layering. The mids are definitely vocal-centric, however.
Treble: The treble on this set is well done. It’s smooth and detailed. As you can see in the graph above, there’s a roll-off, but those peaks enhance audible detail. With string instruments, it can sometimes sound a touch sharp, but I didn’t find this to be an issue outside of classical music. Treble sensitive listeners should definitely take note that dropping a few dB around 7kHz may be necessary.
The treble tuning is perhaps not as well extended as some of the tribrids I’ve had on the review desk (like the Xenns Up or Monarch Mk. II), but costs a fraction of the price. I find the treble to be very clear and enjoyable, however, and would choose it over the similarly priced Mangird Tea 2.
Technical Performance, Soundstage, and Imaging: The Vulkan perform well for their price point in technicalities. They offer plenty of detail across the frequency range and have a tactility and textural quality that I really enjoy (thank you, sub-bass!). The soundstage isn’t particularly wide, but the layering within is quite good, so you don’t have any trouble picking up individual instruments or sound sources. A wider stage would have helped the Vulkan in this department, but DUNU has done well with what they have here.
Gaming: The Vulkan aren’t earphones I would recommend for gaming. The smaller soundstage impacts your ability to locate sources on a 3D field. Stereo imaging is quite good, so this will be less of an issue for single-player games, but you’ll need to rely on a software solution like Dolby Atmos to support positional awareness in games.
Overall Impressions and Final Thoughts
The Vulkan were exciting earphones to review. They were the first earphones I had ever heard that used this particular driver configuration, and the sound engineers at DUNU did a great job with leveraging its two dynamic drivers. At $380, they don’t come cheap and wouldn’t be my first choice for gaming, but are a solid performer for slipping away into your favorite music.
The product described in this article was provided by the manufacturer for evaluation purposes. Articles may include affiliate links from which we may earn a small commission to help support the site. Authors do not earn affiliate revenue or commissions.