The Unique Melody MEXT is rated at 16Ω and 108dB SPL which places it a bit below super sensitive IEMs such as the Andromeda 2020 and EE’s Zeus but on par or slightly more efficient than their MEXT series of monitors that use electrostatic drivers.
That means most DAPs and some good dongles will drive the MEXT just fine on either low gain medium volume such as the FiiO M17 and the Lotoo PAW Gold Touch and on high gain and medium volume for dongles such as the LP W2 and the Cayin RU6. Background hiss will not be an issue with the MEXT with black backgrounds on all of our tested sources.
The only difference and it is something I picked up on when comparing the MEST V2 and the V2 is the treble presence. the V2 has slightly less compared to the V1 with the MEXT having less than the V2. That might lead to a perception that the MEST series is louder given our ear’s sensitivity to treble presence.
Note also, the UM Copper M2 has a slightly better dynamic range and lower resistance compared to the MEXT’s M1 cable which might also reduce perceived loudness at certain volume levels.
Given the rounded and bottom-up sound signature, I had a strong preference for pairing with dynamically strong reference sound signatures or sources with a relatively clean and snappy tuning.
Overly warm or smooth-sounding sources tended to sound too dense and closed in. You want to give the MEXT a chance to breathe without taking away the impact of that excellent dynamic driver and OBC tech behind it.
For example, the two best DAP pairings for me were the FiiO M17 and the LP P6 Pro with the LP W2 being the most worthy dongle selection. All 3 had a reference character to them that wasn’t overly warm with the P6 Pro providing the best textural detail and balance of the three.
The M17 did very well in extending the treble expansion as well as bringing some excellent dynamic impact on the low-end. The M17 can tread a fine path between clarity and sharpness with that THX amp inside but its clean sound signature is a perfect pairing to the dense and rounded MEXT tuning.
I have to also point out that MEXT can scale a little also. The MEXT dynamic driver did sound a little tighter and more impactful on the M17 compared to the W2 dongle. The W2 is also clean and clear sounding with a good treble response when paired with the MEXT but the bass performance was more neutral and less distinct.
Unique Melody MEST V1
This is the first monitor in the market to feature bone conduction and proved to be a very popular release back in 2020. You can read our review of the V1 here.
The original MEST, much like its successor, is a tribrid monitor unlike the hybrid design of the MEXT. That means the inclusion of electrostatic as well as dynamic and BA drivers as opposed to just BA and dynamic.
The precise grouping is a single 10mm dynamic driver for the lows, 2 BA for the mids and upper mids, 2 BA for the highs, and 2 Sonion electrostatic drivers for the ultra-highs. The MEXT mirrors that except for the e-stat drivers for the ultra-highs and instead relies on the 2 BA for the highs to complete the top-end extension.
As a result, the 4-way crossover inside the MEXT is a little simpler in implementation compared to the 5-way inside the MEST V1. What may well be more advanced is the MEXT OBC or original bone conduction technology which is an evolution of the original ceramic piezoelectric layer inside the MEST.
Instead of plates adding an additional layer of response across the mids and highs from 1k upwards, we now have the new copper voice coil/N52 magnet combination with a vibrating steel layer covering a much wider range and in particular the lows from the dynamic driver.
The physical positioning of the bone conduction technology has also changed with the new OBC driver to the rear and close to the ear bone and the older version more towards the plate side.
Ratings wise the MEST V1 is a little more resistant at 23Ω but more efficient at 113dB SPL. In our real-world testing, however, the MEXT proved to be slightly more sensitive to current and voltage swings and I presume that is due to the lack of the Sonion Electrostatic drivers which can be harder to drive.
Design-wise the older custom MEST V1 has a larger form factor compared to the custom MEST V2 but it’s a lot closer in size to the custom MEXT version. Again, I suspect the difference here is in creating the additional room for the OBC driver to the rear rather than the e-stat drivers which tend to sit closer to the nozzle.
The nozzle length is virtually the same with both offering a deep or long nozzle fit. Despite the MEXT using 2 venting ports, I felt both custom samples offered the exact same level of isolation and because they are custom fits the comfort levels did not differ one iota either. These are perfect fits for my ears as they should be.
There are some design evolutions with the MEXT now offering a standard flush 0.78mm 2-pin fitting compared to the more awkward protruding stem 0.78mm 2-pin sockets on the original MEST. Cable rolling is a lot easier though with the excellent M2 cable I don’t think you need to rush out and upgrade your cable for the MEXT.
Speaking of cables, the M1 on the MEXT is a step up design-wise on the older MEST cable. However, it is a 4-wire OFHC compared to the original 26AWG 8-wire SPC though in truth I found the performance of both competitive with just a marginal switch up in treble presence from the SPC MEXT cable compared to the smoother M1 copper.
You can still ask for the MEST carbon fiber weave design for the MEXT, the designs are interchangeable but note there is an additional $60 I believe for the Z18 purple and blue mix for the MEXT sample we are using.
The original MEST has the more balanced ‘audiophile’ tuning whereas the MEXT delivers the colored and ‘fun-sounding’ performance.
There is a very clear difference in the bass quantity and timbral warmth between these two with the MEXT offering more sub-bass elevation and physicality, no doubt aided by that OBC driver. In contrast, the MEST is much more controlled though not without some mild elevation from 20Hz to 200Hz.
The MEXT stays relatively elevated so even though the curve drops slowly to almost 2-3k it still sounds north of neutral. Mid-bass to lower-mids have a lot of presence and a lightly rounded tone for both instrumental and vocal timbre.
The MEST is a lot cleaner and lighter in body with a more neutral mid-bass and more nuanced lower-mids rise. There is more bass-to-mids separation and less warmth running through the MEST mids timbre as a result. It also has a more natural balance from 1-2k for male vocal presence whereas the MEXT is more dipped up to around 3k for chest and some mix pitching vocals.
Countertenor and whistle vocals as well as some higher pitching percussion do a lot better with the MEXT’s stronger 4-7k or upper mids rise though the timbre is still to the liquid-smooth and dense side due to the comparatively relaxed treble performance.
Here the MEST’s highs BA and electrostatic combo reach a bit further and offer a brighter treble mix which in turn injects some comparative sweetness into the midrange timbre. The MEXT still sounds the more rounded and darker of the two customs.
Staging-wise, the MEXT is much deeper and the more powerful of the two whereas the MEXT pushes your attention more to the cleaner mids and treble with a better resolution and a decent bass fundamental to balance it out.
Unique Melody MEST V2
The MEST V2 was launched in 2021 featuring some physical and engineering improvements over the original as well as a new tuning profile. You can read our review here.
Much like the original, the MEST V2 is a tribrid 9 driver custom IEM using a mix of electrostatic, dynamic, and electrostatic alongside a single bone conduction driver. The MEXT is missing that electrostatic dimension hence its 5+1 driver configuration with a 4-way as opposed to a 5-way crossover.
On the flip side, the MEXT uses the new OBC bone conduction tech with its n52 magnet and vibrating steel layer and as opposed to the MEST V2’s dBC-s dual-sided Bone Conduction System. This is essentially a double-sided piezoelectric bone conduction driver placed between two supporting plates with a ceramic-coated vibration board placed at the center of the driver.
The position of the MEST MKII bone conduction is also similar to the V1 residing just below the plate and relying on the vibrating waves seeping into the main shell. The OBC inside the MEXT is closer to the rear of the shell and the ear bone itself giving it a much greater level of focus, though this might be more relevant to the low-end performance.
The MEST MK II is rated at 12.3Ω and 112dB SPL which is a little lower than the MEXT which has a higher 16Ω impedance marker and a not as sensitive at 108dB SPL. In our real-world testing, I did not detect too much of a difference between them for volume matching purposes using a FiiO M17 and the HiBy RS6.
This particular custom MEST MKII sample has a similar carbon fiber design only this time with green flakes instead of red. Otherwise, the effect is the exact same, a slightly more muted visual though very complex versus the enhanced pop of the purple and blue swirl of the MEXT aesthetics.
The shaping and nozzle length is the exact same as each other given they are custom designs, however, the actual external dimensions of the MEXT are bigger than the MEST MKII. You get a little more main shell depth and a slightly longer faceplate.
It is not a huge difference but side by side it is noticeable with my suspicion again that the new OBC coil size and placement is more space-hungry to work as intended whereas the bone conduction on the MEST MKII is positioned closer to the faceplate.
Comfort and isolation are identical since both are vented hybrid driver custom designs that should come as no surprise. The only difference is the little metal plating lining the single vent of the MEST MKII as opposed to a dual non-plate plate lined finish of the MEXT.
Qualitatively, the supplied M2 cable with the MEST MKII is the better cable. It has a slightly nicer PVC finish, a thicker wire gauge, and a better quality of copper wiring. Aside from that, the M1 is quite similar including matching barrels and connectors with the same termination options.
The MEST MKII is closer to the MEXT compared to the V1 in terms of general coloration. And yet, it also could be considered a little more balanced sounding with its additional electrostatic monitors providing more upper treble sparkle which in turn puts a bit of a brighter spin through the midrange timbre.
The low-end on the MEXT has a lot more rumble and warmth. It’s visceral and deep sounding compared to the MEST MK2’s performance. I was actually expecting this to be a lot closer given my memories of the MEST MKII’s enhanced sub-bass presence compared to the V1 but nope, the MEXT still has the better body.
I actually think the curve of these two is not that different from the mid-bass through to around 2-3k. Both are working from a north-of-neutral line that gently fades into the mids so both offer a stronger lower-mids presence.
Where they differ is the coloration with the MEST MKII benefitting from a stronger upper treble from the electrostatic drivers that drive in a bit more air with a pristine quality to higher pitching notes. The MEXT is more relaxed in this region, not quite as airy and smoother sounding through the mids as a result.
The upper mids on the MEXT are more elevated though so it can sound a little closer in terms of imaging compared to the MEST MKII seems the cleaner with superior clarity and separation.
Staging-wise, the MEXT wins it for depth and power sub-100Hz with the MEST MKII offering a bit more complexity and control on the mids and more extension in the highs. A small note also on the cable differences, the M2 does offer a little more dynamic range for me over the cheaper stock MEXT M1 cable.
qdc Anole V6
This is one of my all-time personal favorites and the first qdc custom monitor I reviewed back in 2019. It’s a different setup from the MEXT but its price point and driver count are very similar.
The Anole V6 is a completely different setup from the MEXT. This is an all-BA 6 driver internal configuration with 2 large or woofer drivers for the lows and 4 smaller BA for the mids and highs.
There are no electrostatic drivers, dynamic drivers, or bone conduction technology. Instead, it has a triple dip-switch tuning system that makes a play on resistance through the drivers to achieve 4 unique tuning profiles.
Those profiles include standard which is a balanced tuning profile, strong bass, and a smooth vocal, profiles that are self-explanatory. The final is a high-sensitivity setting that lowers the resistance and ups the top BA driver treble presence.
Because they make a play on the resistance levels the rating of the Anole V6 is variable unlike the fixed rating inside the MEXT. It ranges from a low of 16Ω for the high sensitivity setting to a peak of 29Ω. The Anole V6 SPL floats a little though not by a huge amount at 106-109dB SPL/mW. As such it’s quite close to the MEXT rating of 108dB SPL.
Like the configuration, the design philosophy of qdc is also quite a striking contrast. qdc does some amazing customizations and the Magic Color of the Anole V6 here is no exception. Everyone has their personal preferences but for me, color pop makes customs a lot more fun.
You could argue, however, that the purple and blue molten or swirl design of the MEXT is the more mature or discreet design and certainly not as polarizing as the almost tropical overtone of the Anole V6 yellows, greens, and reds. Both to me have their pros and cons but certainly, both are excellent designs in their own right.
Both have similar comfort levels with the Anole V6 edging it a little in terms of isolation given it’s an all BA design and does not require any shell venting which the MEXT has.
A few technical differences for me on the Anole V6 that might make it a more difficult choice and that’s its reversed polarity extended 2-pin 0.78mm connector system. That makes it hugely difficult to cable roll without an additional adaptor or qdc-specific reverse polarity connector on the cable itself.
Which might be ok except for the supplied cable with the Anole V6 being a decidedly average choice. Both it and the MEXT UM Copper M1 are 4-wire though the Anole V6 wire itself is SPC as opposed to OFHC copper inside the MEXT.
I suspect though the gauge on the Anole V6 wire is lower than the MEXT and most certainly the finishing is of lower quality and less attractive looking.
I think the Anole V6 does quite well for a BA bass low-end performance but you do have to push up the switches to strong bass to get a more fulsome response and even then it’s nowhere near as visceral or deep as the MEXT dynamic driver low-end.
The Anole V6 is tighter on the low-end with less bloom courtesy of a more pronounced u-shaped delivery whereas the MEXT is more of a gentle L- up to 2-3k. That means more warmth, upper bass, and lower-mids presence, and a much more rounded and denser sound quality to the MEXT to the mids whereas the Anole 6 sounds more balanced, but cleaner and lighter also.
The 1-4k range is more elevated compared to the MEXT which brings up the 3-6k region a bit more to the fore to balance out the stronger sub-bass levels. Vocals are cleaner on the Anole V6, not as rounded or as ‘broad’ in their texture and sustain. Sibilance is a little more prominent on the Anole V6 but still sounds quite sweet and natural through the mids overall.
The Anole V6 also has a bit of a 6-8K peak which is fairly narrow, producing a little more BA energy in the percussion timbre. The MEXT percussion timbre is smoother and more liquid to my ear with a bit less contrast but a more pleasing texture.
In terms of staging, the MEXT is more bottom-up with your ear drawn to the deeper sub-bass and lower-mids performance which is quite forward sounding. Whereas the Anole V6 is more balanced with a decent punch and a lower-mid instrument imaging that tucks in behind a more forward vocal and upper-mids percussion bias.
The Unique Melody MEXT is the company’s most confident and complete use of its bone conduction technology to date. This is a full-blooded tasty bass-centric performer with enough balance in the mids and vocals to please those who like their music to be beefy yet inviting.
Clearly, it’s not quite MEST levels in terms of treble extension and absolute clarity but then again I doubt that should be surprising given it’s a tier below their award-winning series and missing those electrostatic drivers.
However, I have a sneaking suspicion the OBC in the MEXT will show up again in either a 3rd gen of the MEST or something even higher-end down the road. It has some serious promise. For now, we get a glimpse of some solid potential in a value for money, highly enjoyable, and physically attractive custom monitor.
Unique Melody MEXT Specifications
Headphone Type: Coil Bone Conduction + Dynamic +Balance Armature
Air Conduction Frequency Bandwidth: 20Hz-23kHz
Vibration Conduction Frequency Bandwidth: 200Hz-7kHz
Sensitivity of Air Conduction: 108dB @1kHz
Sensitivity of Vibration Conduction: @1kHz 5m·N | Peak @400Hz 79m·N
Crossover: 4-way Crossover
Driver Counts: 6 Drivers
Configuration:1 Coil OBC Driver + 1 Bass Dynamic Driver + 2 Mids BA Drivers + 2 Treble BA Drivers