Unique Melody MEST MkIII Review: Moments of Magic

Unique Melody MEST MkIII


Once a name firmly rooted in the boutique IEM scene, Unique Melody was brought into the spotlight with the release of the MEST three years ago. What was so special about the MEST? The fact that it was one of the very first IEMs to use bone conductor drivers. While dedicated bone conduction earphones aren’t a new concept (see Shokz earphones), Unique Melody’s approach was to combine the technology in concert with the usual amalgamation of drivers found in IEMs. 

Needless to say, there has been significant discussion on the actual impact of the bone conductor driver. But few would deny that there was something special about the MEST. Having reached cult status, Unique Melody capitalized on its success with the MEST MkII and the topic of today’s review: the $1,920 MEST MkIII CF. As I’ve only briefly heard the original MEST and haven’t heard the MkII, I’ll be looking at the MkIII with fresh eyes as a competitor to the thriving high-end IEM scene.

Source(s) Used: Ferrum ERCO Balanced DAC & Headphone Amp and Apple USB-C dongle

The Unique Melody MEST MkIII CF was sent to me for review by Leo at Unique Melody.

Note: The CF at the end describes the carbon fiber shell design. There is no “normal” version of the MkIII. This review unit was provided to me by Leo at Unique Melody.

Note 2: The red variant is more expensive at $2,360. You can get a cheaper version of this blue one for $1,600 without the cable and $1,900 for the red version. It seems like Unique Melody is having issues with sourcing the materials for their shells.

What we like

  • Excellent resolution and microdetail
  • Great soundstage and imaging
  • Pleasant midrange note texturing
  • Relaxed upper mids and softer treble

What we don’t like

  • Extremely eartip dependent
  • Bass quality is lacking
  • Genre dependent
  • Driver flex and stiff stock cable

What’s in the Box

Open up the box and you’ll be greeted with an Einstein quote of all things. Once you wrap your head around whatever the marketing guys were thinking, this is what you’ll find:

  • An aquamarine faux-leather cable clip
  • A large aquamarine circular carrying case where the top slides vertically open
  • A microfibre cleaning cloth and separated IEM pouch
  • Two sets of Unique Melody’s new “Transparent Eartips” in S/M/L. One set has small perforations to alleviate pressure (Open Tips) while the other does not (Petal Tips). They’re grippy like the AZLA Xelastec tips except much softer. However, the length of their nozzle is extremely short and thus severely limits them on the IEMs that it can be used on. I’m not a fan.

  • A beautiful cobalt blue 4.4 mm PW Audio cable. Below the Y-split is a flat fabric sheathed cable and above are single-core shielded black cables. The metal connects feel absolutely premium. Unfortunately, this cable is extremely unergonomic. While there’s practically no cable noise (which does deserve credit), the stiffness of the fabric half makes it extremely unwieldy to use for anything outside the desk. The feedback from this stock cable was so negative that they actually offered a cable-less version for over $300 cheaper.
  • The MEST MkIII itself. While the size of the shell itself is actually fairly reasonable, nozzle diameter is yet another massive 6 mm affair and I did start to feel it after using them for a while depending on the tips I used. Annoyingly, the MEST MkIII also has driver flex. I had no issue with the weight though. Aesthetically, the gold-rimmed translucent blue shell makes it look the price, though I would say the carbon fiber streaks embedded in it are hardly noticeable unless you’re right up close.

In case you were wondering, the MEST MkIII sports an exotic driver combination of 4 electrostatic drivers (EST) + 4 balanced armatures (BA) + 1 dynamic driver (DD) + 1 bone conductor (BC) driver. In particular, Unique Melody claims the BC driver operates in the range of 500 Hz to 16 kHz. If you’re not sure what this all means, don’t worry. What’s important is how it sounds.


First things first. Change the stock tips. The MEST MkIII sounds awful with them. I generally review with stock to be consistent but I had to make an exception here. Once you find something else that fits, the MEST MkIII opens up as a bassy, relaxed sounding IEM. It’s a pleasantly colored listen that won’t be winning any awards as the best IEM in its class but does provide a unique enough listening experience that I can see why some enthusiasts have been eager for the “MEST magic”.

Measurement taken with an IEC-711 clone microphone. Comparisons can only be made relative to other measurements taken by this specific microphone. A peak at about 8 – 10 kHz is likely an artifact of the measurement rig and may not exist as depicted here. Measurements above 8 kHz are not accurate. If possible, reference multiple measurements. The Audio File's IEC-711 clone target is currently in the works.

Here is the measurement of the MEST MkIII using the stock Petal Tips. For my unit, the channel matching isn’t great in the mids unfortunately. It’s not super noticeable in actual use but is a shame to see in a product that costs almost two thousand dollars. Notice that large 8 kHz peak? While part of it is an artifact of the measurement rig, there is some harsh peakiness in the mid treble with these tips.

It’s very important to note that the MEST MkIII is extremely susceptible to the tips you use with it. Here’s an example using the Final Audio Type E tips:

There are significant changes in the treble and even the upper mids are affected. I’ll post a few more examples in the Appendix section if you’re interested, some with more drastic effects than others. The key takeaway here is that the MEST MkIII is an IEM you will definitely want to tip-roll. For this review, I generally used these Final Audio tips as they alleviated any comfort issues I had.


From the frequency response graph we can see that the MEST MkIII has a healthy amount of bass. On paper, it’s quite a nice shelf. There’s about 8 dB at the subbass and slopes off cleanly at 300 Hz. Its subbass rumble and extension is excellent. However, given the very modest upper mids presence, the bass can overstep its boundaries. There is a slight hint of bass bleed into the lower mids. Its character is undeniably that of a dynamic driver - rounded transients with a naturalistic note decay. Note definition is very good on the bass guitar with pleasant texturing but a little fudged on the drums. Its character is big and bodied, with more of a pounding sensation rather than boom or punch. The volume on display creates a sense of scale. But in terms of impact and dynamics, the MEST MkIII doesn’t deliver much beyond quantity. Its bass quality just isn’t quite up to par with others in its price range.


In an era where IEMs are converging around 7 - 8 dB of upper mids, the relaxed midrange of the MEST MkIII is rest for the weary. What surprises me about the MEST MkIII is that despite having such a low pinna and significant bass presence, the midrange is perfectly clear. I never get the sense that vocals are buried in the mix. There’s warmth to the tone but it’s not from a richness in the lower mids. Instead, it’s a pulling back of the vocals, as if the singer is standing a foot away from the mic and creating a natural sense of space. This sort of tuning reminds me quite a bit of the DUNU SA6, except taken one step further.

Where this IEM really shines for me is the texturing of its midrange instruments. As I’m casually listening, when I least expect it, the MEST MkIII creates moments of magic where certain notes are rendered in such a unique way that I start to pay extra attention and ask “Did that really just happen?” I notice it most often with acoustic and electric guitars and stringed instruments like the violins. The microdetails captured as these strings vibrate combined with the midrange warmth of the MEST MkIII delivers just such an enjoyable experience.


The treble of the MEST MkIII has a soft sparkle to it. There’s a little bit of crispness to the hats and cymbals, there’s a fine balance of shimmer and washiness to the decay, and there’s a relaxed sharpness to its transients. It creates a light touch of emphasis on treble notes to gently integrate them into the music without sacrificing detail. Personally though, I could use a little more treble brilliance as it does come off as slightly dark due to the upper treble roll-off. I must emphasize however the importance of having the right tips. This soft treble is easily replaced with peakiness and harshness on certain tips, say for example, the stock Unique Melody tips the MEST MkIII comes with.


The MEST MkIII’s presentation is where it steps up its game. There’s plenty of stage width and importantly, stage depth. Notes are a little more concentrated to the center than evenly diffused, but the MEST MkIII’s depth creates an added sense of layering and space. Sadly, this center image is a little less defined than I’d like due to my unit's channel imbalance. That said, imaging for panned instruments is very good, making full use of the stage width while exhibiting nuance in more central notes. For example, I can visualize how the drumsticks are moving around as they lightly tap different parts of the ride cymbal.

Resolution is excellent. It’s not so much that unnoticed passages are now revealed but moreso that microdetail and extra notes quietly present themselves. It’s most noticeable with midrange instruments, though some treble notes take advantage of this as well. It perfectly complements the texturing I noted earlier. It’s here that I suspect the bone conductor driver is doing its job, echoing the reproduction of the other drivers to impart an added layer of musicality on the MEST MkIII.

The MEST MkIII is not a generalist. Hard hitting rock and metal are its weakest genres; the lack of pinna gain, abundance of bass, and softer treble means it can lag a little on clarity. Pop generally works well thanks to their very high level of production and the more digital/electronic nature of its instruments. Instrumentals are a little hit-or-miss depending on the recording. Acoustic and jazz pieces are superb. Full-scale orchestral sets can be a little unfocused. This isn’t to say that the MEST MkIII only works on some genres. Just that it will really shine on some and fall a little flatter on others.

Should You Buy It?

Not unless you’ve tried the other options. The MEST MkIII is a great collector’s IEM with plenty of flavor. But I wouldn’t have it as a top contender as the first and only IEM someone would own. I would look at it from the perspective of someone who wants just something a little different from the rest of the market. From my short audition of the original MEST, the MkIII is a much more “normal” sounding IEM that doesn’t have quite the same feel as its predecessor. While it does show me a few moments of magic, the MEST MkIII doesn’t step too far out of the realm of familiarity.

Honestly, my biggest complaint with the MEST MkIII is its price. I have to remind myself that it costs almost $2,000 rather than the $1,000 or so pricing of the IEMs I’ve been looking at lately. While the MEST MkIII has a pleasant enough presentation that I’m considering making it my daily driver, these strengths aren’t enough to completely cover its weaknesses. And simply put, the bar for a high recommendation in the price bracket Unique Melody wants the MEST MkIII to play at demands a strong all-around performance. But if this review still convinced you, let me suggest getting the Unique Melody MEST MkIII without the cable for a $300+ discount.

- Fc-Construct


Here are a few measurements illustrating just how much the sound changes with different tips on the MEST MkIII. Obligatory disclaimer: measurements in the treble past the 8 kHz resonance peak are not accurate. These graphs are meant to compare how there might be a change; don’t take the exact frequency and volume differences too seriously.

Stock (Petal) vs Divinus Audio Velvet Tips

Other than the Final Audio E tips, I used these Divinus Audio Velvet tips the most. It’s a good option but the Final tips had a bit more sparkle and were more comfortable.

Stock (Petal) vs Spinfit CP-100 Tips

Quite similar in performance to the Final Audio E tips, both in comfort and in sound.

Stock (Petal) vs AZLA Sedna Tips

Surprisingly, the AZLA Sedna graphs almost identically to the stock tips. I can confirm that there is a harsh mid-treble peak but in terms of presentation and soundstage, the AZLA Sedna’s are much much better and similar to the other tips than the stock UM tips.

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