Unique Melody--The Multiverse Mentor Flagship IEMs


Previously known as gangviolence
The Multiverse: The Search For Evidence
Pros: Elegant Design
3D Holographic Imaging
Balanced Tonality
Cons: Price
Cable Microphonics
Unique Melody Multiverse Mentor

About Me
: I am passionate and thoroughly find joy in providing feedback on products to help other hobbyists along their journey. Trust only in YOUR ears. Music has been, and will continue to be, a huge part of my life. My escape from the frustrations and static of everyday life. I typically listen to Metal (progressive/ djent/ deathcore/ hardcore) alternative and classic rock. Music with meaning, emotion, and polyrhythms! Music dedicated to pushing the limits of what we thought was possible.

Introduction: For me, Unique Melody holds a special place in my heart. After finally reaching a level of financial freedom that allowed me to dip my toes in the ‘+ kilo buck’ market, I purchased the Mest MKII. I had never experienced anything like it... The immersion, the detail, the BCD! An experience that completely altered my understanding of what was sonically possible.
Overtime, as my preferences evolved beyond the MKII’s capabilities, I moved on. The MKIII was an outstanding addition to the ‘Mest’ family, but it unfortunately failed to hold my attention for more than a couple months. I needed something more. Something unlike anything else.

Behold, the Mentor Multiverse


Product Overview: Unique Melody Mentor Multiverse (MM)
- Retail: (UIEM) - $4499/ (CIEM) - $4999
- Driver Configuration: 12 Balanced Armature Drivers + 1 Frequency Shift Piezoelectric Bone Conduction Driver
4 low frequency (BA) + 2 mid frequency (BA) + 2 mid-treble (BA) + 4 treble (BA) + 1 BCD
- Sensitivity: @1kHz 114dB
- Impedance: 22 Ohms
- Frequency Response Range: 20Hz-40kHz
- Stock Cable: Deep of Universe Shielding (Custom Collaboration)
Specs: Soft PVC and Nylon Shielding/ Copper and Silver-Plated Copper/ 26 AWG/ 4 Wires

If you’re interested in purchasing a set, please find the link below.
MusicTeck - Unique Melody Multiverse Mentor

Unboxing Experience (5/5)
I have always been a fan of Unique Melody’s packaging. Compact, ergonomic, and easily storable. I appreciate the use of embedded magnets to retain the top cover in lieu of velcro and the fact that all accessories are stored in an easily accessible drawer. No molded foam to remove or additional flaps to damage and deal with. The IEM’s and cable are safely stored in a beautiful navy-blue leather case.

  • UM “ESP” Double Drawer Blue Gift Box
  • Pair of UM Multiverse Mentor
  • Deep of Universe custom cable with oval wire clamp
  • Dignis Navy Blue Leather Case
  • Premium Grey Cleaning Pad
  • Eartips - Silicone rubber SS/MS/ML - Silicone S/M/L
  • Warranty Card

Build Quality (5/5)
Starting with the overall aesthetics, the Multiverse’s shells are gorgeous. The blue and purple shell face is elegant, simple, and just plain intoxicating to look at. The shell is made of an aviation grade carbon fiber, a ceramic outer frame, and 3D carved faceplate. The overall construction is solid, ergonomic, and lightweight. No complaints whatsoever. It really is hard to believe they crammed 13 drivers into this thing.

Fit (5/5)
The shape and size of the Multiverse is fantastic. I experienced zero discomfort or fatigue at any point while listening. The nozzle size is average, all metal, and features a changeable filter. Insertion depth is rather shallow. In a culture of ‘bigger is better’, IEM’s are growing insanely large and require you to have either ‘perfectly average’ ears or purchase customs. The universal MM is literally perfect for me.

Cable (5/5)
You can always count on Unique Melody to provide a worthy cable pairing with their flagships. The PWA x UM ‘Deep of Universe’ is no exception. The cable is a dark blue, traditionally braided 4 wire, with custom all metal hardware and pre-shaped ear hooks. You will notice some microphonics when handling, but I typically save jumping jacks for after my listening sessions. For what it is, the cable has good ergonomics.

Accessories (5/5)
Case: Blue premium Dignis leather case w/ soft removable partition for storing IEMs separate from cable. The case is quite large but that all comes down to preference and use case. I typically transfer all my sets into Pelican cases.
Cable Organizer: Leather, oval shaped wire clamp
Eartips: Includes (1) set of signature blue-heart core silicone ear tips (S/M/L) and (1) set of Azla Xelastec ear tips (SS/MS/M).
Additional: IEM Protective Sleeves/ Premium cleaning cloth/ Replaceable filters
Wishlist: None

Sound (9/10)
Personal Taste: Bass. I need to feel my music. There needs to be a distinct separation and accurate layering of instruments. I need to hear that bass guitar! This is the sonic link between the rhythmic and melodic elements in music. Vocals are generally less important to me but need to sound natural. Treble should be well extended with an emphasis on presence, air, and overall detail retrieval. I find myself somewhat sensitive in this region and absolutely despise shouty, sibilant IEM’s.


(Measurements provided by Elise Audio)
Disclaimer: I want to emphasize that graphs do not paint the entire picture. It is imperative that you know the aspect ratio of the graph, y-axis range, normalization used, and how much octave smoothing was used. FR graphs are a great visual reference when trying to communicate certain aspects of an IEM’s tonal balance, but a great looking graph does not always mean a great sounding product.

I listened to a wide range of music while developing my assessment. Before putting anything down on paper, I spent over 50 hours casually and critically listening from various sources. I found the Multiverse to be well balanced, naturally revealing, with a W-shaped sound signature.

Bass: When it comes to low frequency driver implementation, my preference has always been dynamic driver’s. In my experience, DD’s provide a better bass response, sound more ‘natural’, and are more durable. Another reason I prefer DD’s is comfort. By design, DD’s are moving air and require venting, which in turn helps in combating pressure build up. For this reason alone, I have not purchased an all BA set since the Symphonium Meteor. It doesn’t matter how great a product is if you can’t be comfortable using it. You might be asking yourself, ‘Why are you telling me this? The MM doesn’t utilize dynamic drivers?’.
Great question! Well, it turns out the MM has implemented some unique solutions to my problems.
- On the top of the MM you will find a vent. During all my testing and critical listening sessions, not once did I experience any pressure fluctuation or discomfort.
- If we can’t move air, let’s vibrate some bones! The bone conduction driver provides a different experience, no question. But the sensation is quite satisfying. Just know, it is critical you find the right eartips and fit to enjoy the full experience.
- The MM’s low frequency tuning is superb. The bass is full, well controlled with absolutely no bass bleed or masking of the mid frequencies. This is NOT for bass heads. Though I did enjoy my time jamming to 2Pac, A$AP Rocky and Coast Contra, I’d still prefer pulling out the Raven’s or Grand Maestro’s for those bass focused compositions.

Midrange: The mid-range is responsible for quite a bit, ladies and gentlemen. I don’t classify myself as a ‘mids guy’ but this region can make or break the overall tonality of an IEM. Luckily, in my humble opinion, this is where the Multiverse really shines. I would say the MM is more ‘musical’ than ‘clinical’. The mid-range is incredibly realistic and detailed. As mentioned before, the mid-bass to lower-mid transition is exceptionally executed. The MM’s lower mids are lean, full bodied, and well controlled. The upper-mids are slightly more relaxed, helping to bring emphasis to the overall clarity and detail the MM is so well known for. Vocals are slightly recessed, natural, and perfectly blended into the mix.

Treble: To test lower treble, I will typically listen to a few acoustic tracks with vocals. I found the MM to be well refined minus a slight ‘tinny’ characteristic with acoustic guitars. To be fair, I’m being critical here. The mid and upper treble has great extension and is full of sparkle and air.

Technicalities: The soundstage and pinpoint accurate imaging capabilities of the Multiverse are truly something special. It's not uncommon for am IEM to have exceptional width or height or depth... But all 3 simultaneously?! The Multiverse has earned a reputation among the audiophile community since it was released into the wild… And I find it to be 100% accurate. Additionally, the MM has great instrumental separation and layering. Overall detail retrieval is among the best in its class.

Eartip Selection
Listed in order of preference
  • Symbio W/ Zeos Render Memory – Best isolation, best BCD effect, improved low-end, treble peaks are tamed.
  • Azla SednaEarfit Crystal - Great isolation, powerful BCD effect, balanced tonality.
  • Azla Xelastec – I have never been a fan of thermoplastic Elastomer. The Xelastec’s provide great isolation and improve low-end weight. BCD effects improved significantly. Treble fatigue issues resolved.
  • Eletech Baroque/ SpinFit CP145 – I experienced minimal effects from the BCD and found the treble to be a bit fatiguing. Overall technicalities were still very strong.

Preferred Source
After testing on multiple sources, my preferred pair up for the MM is the Cayin N7+C9 stack (Class AB/ NuTubes/ L Gain). I found this source chain to provide the most expansive soundstage and a natural/ uncolored tonality. Other sources tested included the HiBy RS6+C9 and A&K SR35+ PA10.

For my comparisons, I wanted to focus on several categories (price (Erebus)/ frequency response (Grand Maestro)/ sound signature (Khoas)). Comparisons were conducted while listening to the same song(s) - Volume matched on the same source chain.


UM Multiverse Mentor Vs. FF Grand Maestro (Frequency Response)
Prelim: For those unaware, the Grand Maestro is equipped with a vocal switch, transforming its renowned V-shaped signature into a more balanced W-shaped tuning. On paper, the frequency response of the MM and GM are strikingly similar. But can the Grand Maestro, jack of all trades, stand up to the all mighty Multiverse?
Fit: It’s undeniable, the Grand Maestro is massive in size and hefty in weight. Though I find them to be comfortable while sitting at my desk, they look absolutely ridiculous in my ears. No question, the MM takes round one.
Sound: The GM provides a more intimate experience. Where the MM’s soundstage expands in all directions, the GM only competes in width. The MM also provides a noticeable boost to imaging. The GM’s dynamic driver provides a rich rumble where the MM delivers a well-controlled punch. Lower mids sound thinner on the GM but both sets sound very natural with exceptional timbre. Micro detail retrieval is great on both sets.
Conclusion: If I had to choose one set based on a W shaped sound signature, I would choose the Multiverse. To me, the MM takes the edge on technicalities and provides a fuller, more energetic soundscape. If your goal is versatility, the GM a great option. It’s cheaper and offers (4) unique tuning configurations that all sound fantastic.


UM Multiverse Mentor Vs. NGaudio Khoas (Sound Signature)
Prelim: The W-shaped signature show down. After purchasing the Khoas a few months back, it quickly became the most impressive IEM I had ever experienced. Well balanced, energetic, expansive sound stage, absolute detail monster. But is it enough? Only one way to find out!
Fit: Both are similar in size, shape, nozzle diameter and insertion depth. I could wear either for hours with no complaints.
Sound: As far as technicalities, both sets are summit tier. Sound stage, resolution, detail retrieval. Both sets provide a solid low-end punch, but the Khoas delivers its bass with a slightly deeper, realistic punch. When compared, the Khoas is more fluid and musical, while the MM is crisp and accurate. The MM has more top end ‘sparkle’.
Conclusion: The Khoas and MM are the two most clinical/ accurate IEM’s i have ever heard. I spent hours switching back and forth between the two and in the end, it all boiled down to preference. Neither set exhibits a strength that the other cannot replicate. If you prefer DD bass and a more polite treble response, Khoas. If you prefer the effects of the BCD and some added sparkle and energy, the MM. Both are exceptional choices.


UM Multiverse Mentor Vs. NGaudio Erebus (Price)
Prelim: A Flagship showdown! Both competitors sport an eye watering +$4.5k price tag but are either worthy? Time to take off the gloves.
: The Erebus is slightly larger in size, but both share a similar nozzle diameter and insertion depth. No issues with either.
Sound: For starters, these IEM’s are tuned very differently. The Erebus provides a similar holographic experience to the MM in less bass-prominent tracks, but when that bottom end gets-a-rockin’, the Erebus struggles to expand. The MM does a great job of maintaining its technicalities at all times. If it wasn’t clear, the Erebus supplies some significant bass. The mids of the Erebus are definitely more linear, contributing to its mild V shaped signature. Vocals are slightly more recessed on the Erebus. Treble has a very similar presentation but a little more ‘polite’ on the Erebus.
Conclusion: I want both of these sets in my collection for completely different reasons. For critical/ detail focused listening sessions, the MM. For more casual/ emotional inspired listening sessions, the Erebus

After the release of the Multiverse, I’d often visit the MusicTeck product page while simultaneously thinking of ways I could budget or sell other gear to acquire and experience the magic. Do I regret not being an early adopter? Not a single bit. The UM Multiverse is no ordinary IEM. But to truly appreciate all the MM has to offer, you first need to understand what you're missing and why you need it. It’s easy to jump into the hobby and buy the most expensive set because everyone tells you it's great but to comprehend and appreciate what UM has accomplished here is no short of remarkable. In closing, yes, I would 100% recommend this product. But I would also recommend taking your time to get here. Appreciate what your audio journey has to offer!
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Nice write up!

This iem is already a classic. The most headphone-like sounding IEM I’ve heard to date and quite the immersive experience with to die for midrange.
just received Mentor, I can say, this is the best all-rounder IEM for now. good job UM.


Headphoneus Supremus
A true masterpiece from Unique Melody!
Pros: Amazing technicalities
Very coherent tuning without flaws
Best BCD implementation I ever heared
Superb bass quality
Big and holographic soundstage
Gripping representation
Great design and build quality
Cons: Maybe the Price?
In this review I'll be highlighting the Multiverse Mentor model from Unique Melody. For many the best IEM from Unique Melody ever and in some circles it is even considered the best IEM worldwide. So we are not dealing with just any TOTL IEM, but with the crême de la crême of IEM development. And my expectations were just as high for this model from Unique Melody. Recently I could already write a review about the MEST MK3 and I found this model very successful. I especially liked the bone conduction driver, which is responsible for a "gripping" sound in the truest sense of the word. Normally, in recent months, I tend to use more dynamic drivers for the bass range. But since the Multiverse Mentor just still contains the BCD, I really wanted to give it a try. And one of my favorite IEMs, the 64 Audio U12t is also always compared to the Multiverse Mentor, as both are a BA based 12 driver IEM. However, the 64 Audio does not have a BCD. Its BA bass is already outstanding for this technology, although it can't offer the punch of the dynamic drivers, which I sorely missed in the end.


The Multiverse Mentor is more or less the successor of the Mentor V3+ and was developed over several years by Unique Melody engineers. The name Multiverse stands for a group of unknown universes that were created after the big bang. With the name Multiverse Unique Melody aims at the fact that the Multiverse Mentor is just the emergence of a whole new development that breaks all traditional technologies and tunings.

The 12 BA drivers are composed of 4 BA drivers for bass, 2 for midrange, 2 for high-midrange and 4 for treble. The biggest innovation is the bone conduction driver, for which Unique Melody has a patent. These drivers are significantly larger than those of most competitors and no other manufacturer uses this bandwidth of 20Hz to 20KHz! This high bandwidth not only makes the bass range more noticeable, but the overall sound is stronger and more focused, all in all you can feel it more. How good I will illuminate later.



The Multiverse Mentor is available in different designs. Mine is the variant in "Blue Purple" and the IEM just looks damn good! The workmanship is absolutely top class. The shell is made of carbon fiber, which is enclosed by a ceramic frame. The faceplate gets its design by using banksias. These are mostly in Australia growing beautiful colorful plants. Each faceplate has its own unique design because it is a natural product. The shell is light and ergonomically shaped, so the comfort is very good. The insulation is also above average. Probably because of the slightly larger diameter of the Nozzle.

To a top IEM also belongs a top cable. And here a specially designed cable was created in collaboration with PW Audio. It is a 4.4mm 4 core copper cable with the diameter 26 AWG, which is silver coated. The workmanship and design are also here at the very highest level and absolutely fit the design of the IEM.

The scope of delivery also includes a high-quality leather case, an oval leather clip for the cable, two different silicone eartips in three different sizes, a cleaning brush, several replaceable filters and a warranty card. The silicone eartips are Xelastec as well as Unique Melody's own tips. By the way, the warranty for the Multiverse Mentor is 2 years from the manufacturer. Most other manufacturers grant only 1 year.


For the sound test I used the Multiverse Mentor with my iBasso DX320 MAX Ti. For this purpose, the gain level 1 is more than sufficient, because the Multiverse Mentor can be driven very easily with its 22 ohms and 114dB sensitivity.

Excited, I plugged it into my DAP and after that came nothing short of absolute amazement and zipping through all my reference recordings. Rarely have I been so flashed by an IEM from the first minute as I was by the Multiverse Mentor. As eartips, by the way, the enclosed Xelastecs fit like a glove and sound for me the roundest of all eartips. The Azla Clear also work very well and bring the mids a little more forward with slightly higher low bass, but the Xelastec of the overall performance are my favorites!

In terms of frequency response, we are dealing with a minimally warm IEM and a special W shape tuning. Here the bass range is somewhat raised. The lower mids as well. With the upper mids and the presence range we have a lowering, which is compensated by increasing the super high frequency range again. All in all, at first glance, not a neutral tuning. I could hardly imagine from the frequency diagram how the Multiverse Mentor sounds, let alone that it sounds so awesome!

Here only one thing comes to mind: Coherence above all! Such a fantastic tuning with which all types of music I have tested (classical, jazz, pop, rock, EDM, metal) sound very good. And the whole thing at the highest technical level, no, the very highest level! The expansive stage, which is more than lushly drawn in all its dimensions, is immediately noticeable. The separation and localization of individual sound events is really holographic. I can concentrate on individual elements right, left and listen to them while in the next moment I devote my attention to another instrument. So far, I've found the Raven to be the benchmark among IEMs in terms of sizing a stage. The Multiverse Mentor draws just as wide, but more holographically than the Raven. The Raven goes a bit further in depth for that. But these two IEMs are absolutely top in this discipline in my opinion.

I listen to a lot of metal and I was mostly curious about the bass range. BA Bass in combination with BCD. Does this work and can it eradicate the weakness that the U12t always carries with it? Yes and this shows that Unique Melody's BCD is simply one of the best implementations of the IEM market if not the very best! However, I haven't heard all the BCD implementations myself, so I won't make a final judgment here. The bass range goes down really deep and creates a rumble, because I have heard so with no BA driver. I am really excited and then up to the midbass, where you can literally feel the bass attacks. In no way is the bass too strong. The exact dose was administered here, which also allows undisturbed audibility in the bass. If you now take a Raven or Radon6 for comparison, they have a bit more rumble in the low bass area. But this difference is by no means as big as for example between a U12t and Raven/Radon6. What I can also hear directly is the speed of the Multiverse Mentor, where it trumps a Raven and Radon6. In terms of bass detail, I can't identify a clear winner here among the three.

Now to the mids and trebles. Voice reproduction and acoustic instruments sound absolutely natural and these areas are harmonized together with the bass to such a perfect match that you just dive into a tapestry of sound and want to listen on and on. When I listen to my reference recordings, I also look for negative points. But I can't find any with the Multiverse Mentor with the best will in the world. This tuning is just extremely brilliant and musical at the same time. In addition, this grip and the authority with which instruments and voices are reproduced. The BCD does a great job here. More bass here or treble and mids there would probably destroy the overall structure. It's perfect just the way it is!

I'm just glad I finally decided to try the Multiverse Mentor. Sure it is a very expensive IEM for 4500 USD. But what you get here for a performance is really unique. A Raven and Radon6 and a Blanc are about the same price. They are all really great IEMs. If you are looking for a musically captivating IEM at the very highest technical level with a superb BCD implementation, you may have found your endgame IEM in the Multiverse Mentor. In my opinion this is an all-rounder and can serve every genre. A true masterpiece from Unique Melody!


1000+ Head-Fier
Unique Melody Multiverse Mentor (The New GOAT)
Pros: -Best in class soundstage & imaging
-Full, thick sound with excellent spacing (thanks to BCD magic)
-Pleasant, easy-going tuning
-Strong dynamics (both macro and micro)
-Easy to pair with sources
-TOTL timbre and realism
-Strong bass for a balanced armatures with nice bass shelf
-Comfortable fit
-Comes with excellent stock cable
Cons: -Price
-Still ultimately BA bass which can come across as pillow-y at times
-Lower midrange timbre can improve

“Hello, Old Friend”: The Comeback

I’d bet (I don’t have a gambling problem, I swear) that most audiophiles (and their wives) have dreamt of the day that they are so pleased with their audio gear that they can just deactivate their HeadFi account with no remorse. But let’s be real-in this universe, it is far more likely that said-audiophile is hopping on to HF to catch up on the 50+ new overnight pages on the Watercooler thread so that they can stimulate their dopamine receptors and salivary glands by indulging into the hype surrounding the newest, shiny multi-kilo product.

Whew-a mouthful. But the point of my exploration of audio addiction is that I was fortunate enough to hit that elusive satisfaction of no longer chasing the dragon. I hopped onto HF here and there in the past 12 months, but happily retired from the IEM/DAP game thanks to the desktop GOAT-Susvara.

However, that freedom from the chains of audio-capitalism is fleeting because as audiophiles, we tend to be tempted by how new technologies can continue introducing revolutionary auditory products (and by virtue, unique auditory experiences). I took a backseat in some of my beloved audio group chats with some key IEM HF influencers, and only would chime in occasionally to troll them about how they better enjoy their new toy because a new one will be coming out 2 weeks later [facetious diatribe about how fast the portable world moves]. But that same tempting curiosity inevitably began to resurface as there was a common IEM that got the new hype label---the UM Mentor Multiverse.

“Honestly sounds like the bird [Traillii] a bit, but better”. “Sure there’s BAs for the bass, but you don’t really notice. It’s the sum of all the parts”. “Mentor HYPE!!!”

Day after day, week after week, the glowing anecdotal comments kept flooding in. So, I decided to take my walk of shame back the portable world and check out what all the hype was about. (Sorry, girlfriend).



Price: $4499

Headphone Type: BA+ Frequency Shift Bone Conduction Driver

Driver Counts: 12+1 Drivers

Sensitivity: @1kHz 114dB

Impedance: 22Ω

Frequency Response Range: 20Hz-40kHz

Crossover: 5-way Crossover

Configuration: 4 Bass Drivers + 2 Mids Drivers + 2 Mid-Treble Drivers + 4 Treble Drivers + 1 Frequency Shift Bone Conduction Driver

Cable: Deep of Universe Custom Cable

IEM from Another Universe:

Prior to MM, I haven’t had much luck with a Unique Melody product. I was not impressed with the Mason/FS, particularly its’ dry tuning with a 6k peak that sharply contrasted the lack of pinna gain. Indigo was a good IEM but felt very bland overall, providing nothing special outside of its unique BCD presentation. So, my skepticism was high going into finally inserting a new set of IEM into my lonely, deprived earholes.

Bass: I’ll start with what I believe is the weakest part of the MM. Balanced Armatures have grown in closing the gap between Dynamic Drivers for robust low-ends, but in my opinion, are still noticeably inferior when you are simply used to a TOTL DD (or even planar) driver for bass.

Mentor’s bass is overall great for its driver. Yes, probably better than the bird from memory, with a strong punch with minimal plasticity. However, it falls short versus a TOTL bass presentation in direct A/Bs by coming across as slightly untextured and lacking a full extension that a DD rumble can provide. For example, on Infected Mushrooms’ “Bliss on Mushrooms”, there is strong macrodynamic energy, but the midbass is not as defined and tight as something like the Jewel or EVO. Yet the bone conduction helps by rounding out the bass to compliment the holographic imaging. It’s still a very engaging listening with a pleasant bass shelf.

MM’s bass successfully does not detract too much from the rest of the IEM’s strengths and instead, provides a seamless low-end to compliment MM’s overall lush presentation. Simply put, the bass won’t be much of an issue if you aren’t A/B’ing to an EE EVO or Abyss 1266 Phi-TAC, and will still likely outperform any other BA on the market for the lows.

Mids: One thing that has ever wavered is my love for mids, and Multiverse just hits the sweet spots here. The midrange to me sounds rather linear, with a pleasant weight to notes (likely due to the BCD). I wouldn’t call the midrange as romanticized or “wet” as the Traillii, but there is special balance of clarity and smooth that the MM just nails.

The upper-midrange is not too forward, yet vocals still have a pleasant presence due to the excellent dynamics and staging. The lower-midrange does suffer in contrast, where drum hits lack the realism or heft that I’d get from an IEM like the XE6. I would attribute this to the BAs used for the lows.

Vocals are natural-sounding, with subtle hints of warmth. Not too forward, not too recessed. Guitars sound excellent with nice crunch and texture. MM’s mids are NOT mid-they are indeed special.

Treble: I tend to not be as overtly critical about the treble region, as long as it’s not too sharp, peaky, metallic and/or lacking extension. I have a slight sensitivity to hot lower-treble IEMs, which is why an IEM like Traillii was perfect for my tastes. And MM, to my ears, also has a similar’ish treble presentation that is full of air (upper-treble) with strong yet pleasant energy in the lower-treble. Cymbals sound great with good timbre, & synth notes have impressive extension. If you found Traillii treble a bit too lax or boring, MM adds a touch of excitement while providing no sibilance.

Along with the vast staging and holographic, 3D presentation, the treble comes across as whimsical. Mentor ultimately has one of my favorite trebles to date and arguably does improve upon the bird in this regard.

Staging/Dynamics: Gotta save the best for last. Let me preface this section with that MM is the closest I’ve heard to an open-back headphone in terms of staging and imaging. If Unique Melody was going for the official bird-kill, they likely knew this is where they could help differentiate themselves from the Gold-Standard Traillii.

As vast as Bird’s stage width was, it falls flat (literally) on the depth. Notes come across as panoramic, i.e., on a vast plain rather than a 3D stage/sphere. Bird’s dynamics also were on the softer side which helped contribute to its unparalleled timbre and romanticized mids, but was not ideal for those who love their hard-hitting music or transients.

MM improves upon both, noticeably. Mentor (along with Aroma Jewel to some extent), truly does have a HP’esque soundstage. It sounds vast, with an impressive left-to-right and centre image.

MM’s notes also have some excellent macrodynamics, with above average microdynamics. Notes have various weights which eloquently pop in and out of a black background, helping the listener immerse in the enveloping stage.

Imaging is great, and strongly benefited by how the BCD adds a unique weight to notes/transients that sound realistic but not overtly heavy or congesting in the stage. In Cultura Profestica’s De Antes, I pulled a Chucky doll and turned my neck a full 360 degrees because I thought I heard a baby crying from behind me in the song’s intro.

Perhaps the Mentor could mentor the Bird on how to do dynamics and holographic/3D staging 😊.​

Which Universe…ahem, Source*, does MM Sound Best?

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Alluding to my earlier diatribe about how fast new DAPs come out, I unfortunately am already feeling like a dinosaur with my AK SP2000 CU and L&P W2. Rockna Wavelight R2R-desktop DAC is also no newcomer, although still an incredible source in today’s desktop landscape.

(Since I initially drafted this review, I have managed to procure an SP3000 SS and the Brise Tsuranagi amp to shed my dinosaur status).

The below sources should paint a general picture about how the Mentor scales and which sound-characteristics may help shape it towards your own preferences.

Mentor + L&P W2:

Comes across as W-shaped, where the BA bass plasticity becomes quite noticeable. There is good midbass but a bit pillow-y sounding. Instrument timbre is nice and overall natural. Stage width is impressive and wraps around your head with strong depth-perception. Notes have a 3D edge that give Mentor that universe-like vast staging.

Mentor + A&K SP2000 CU:

Overall an excellent pairing. There is a much better bass rumble and extension than on the W2, although not completely alleviating that BA’s undetailed midbass slam despite its nice quantity. Mids are more euphoric and forward-sounding as the CU tends to do for most IEMs. Dynamics remain impressive, almost like a loose-bag of fun versus something more “tight” like the Jewel.

Mentor + A&K SP3000 SS:

At first, I found the combo a bit bright/unengaging, but that would be the price to pay for the soundstage boost, detail, clarity and dynamics that the SP3000 offers over its SP2000 Copper little brother. Generally, the Copper version is warmer which helps for those lush mids, but the SP3000 really helps elevate the MM into a grand-sounding IEM that is true-to-form for TOTL performance. Nice bass despite the-discussed BA shortcomings, natural-sounding vocals, and extension for days in the treble without ever being sibilant.

Some would call this the modern-day GOAT:goat: pairing. I think I'd agree.


Mentor + SP3000 SS LO’d into Brise Tsuranagi Amp:


At first I wasn’t expecting much (nor did I hear any true benefits), but adding the AMP into the Line’d Out SP3000 really clicked after an hour or so. There is a slight drop in stage width, but more depth and height, with a fuller sound while retaining technicalities. The sound becomes richer with a slightly warmer timbre that adds pleasant color to the SP3000’s neutrality. There is also better PRAT as I felt myself tapping my toes more to the music.

There is a bit of a midbass boost which in this case, I wasn’t too much of a fan because BAs and midbass do not go well IMHO. It’s one of those cases where I rather the subbass detract from the compromised, pillow-y midbass.

But all-in-all, the Tsuranagi adds a lovely musical component to the already masterful MM. I would definitely recommend checking it out if you want to thicken up the MM’s sound.

Mentor + Rockna Wavelight R2R Desktop DAC & Ferrum OOR/Hypsos AMP Stack:

Some IEMs don’t really benefit from extra power, some do slightly, and some quite noticeable. I didn’t expect much here since usually DDs benefit the most, but boy was I surprised.

R2R + BCD is a magical combo. The staging and instrument separation all opened-up noticeably, allowing more space in between notes. The stage width expands as far as I’ve heard on any IEM. Treble becomes silky, with excellent clarity, energy and transparency-yet smooth. Midrange remains engaging without being too smoothen over as it occasionally did with the SP2k CU.

So does the MM scale when you feed it special stones from other universes? To my ears, absolutely. Would love to hear how it sounds with high-end R2R DAPs like L&P LP6, RS8, etc.​


Yes the MM price is high, but I have to commend Unique Melody for pairing it with a great-synergising cable. When trying the bird’s PW 1960 4-wire, the Mentor lost some of its musicality and lushness. There was a bit more upper-mid centric focus for energy but the overall coherency of the IEM began to falter. Stock cable was also fuller-sounding than the 1960-4 wire.


The Brise Audio Yatono 8 Wire is an excellent combination that smoothens out the MM’s transients a bit while retaining a black background and detail. There is a bit more warmth that adds musicality to my ears. Bass becomes tighter and imaging feels a bit more precise. Mids are pushed forward a touch more. I really like this synergy but had significant issues with the fit and weight of the cable which ultimately did not work for my ear anatomy. Similar to the Tsuranagi AMP, Brise’s Yatono 8w also thickens up and musical’ifys (is that a word?) the MM. :yum:

Summary: The Multiverse’s Exciting Potential

4F7E9D12-D6B1-4E0B-9588-E9262DE74762 2.JPG

As George Constanza emphatically once said, “Every time I think I am out, they pull me back in!”

I thought I was out---a broke audiophile happily listening to his gear without the temptation of the HeadFi’s seductive siren calls. Through headphones such as Susvara, Abyss 1266 Phi & Meze Elites, I had hit that meme’d endgame, which diminished my itch to constantly upgrade to the newest product. But Unique Melody's Multiverse Mentor has been the best IEM I have heard that can arguably rival these headphones. When they are in my earholes, I forget that there are two little transducers conjuring up such an engaging, immersive sound. Whatever bone conduction magic UM has inserted into them has my own bone conducting in full-frequency response.


Unique Melody has truly blessed us a unique product from another universe. The Multiverse Mentor redefines how vast and engaging an IEM can sound. There is a cosmic soundstage that engulfs around your head with musical joy. Dynamics are great, imaging is world-class, and although the bass does suffer from its driver’s limitations, it complements the MM’s overall mesmerizing tuning.

Probably the best IEM in the game at the moment.


Ex-Bird Lover.
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Do you rank the UM Multiverse Mentor above all the below IEMs in overall score/preference?
-Rhapsodio Infinity Mk2
-Rhapsodio Supreme Mk2
-UM Mest Indigo
-Aroma Jewel
-Elysian Diva
-Elysian Acoustic X
-Vision Ears Erlkönig
-Oriolus Traillii JP
In a quick summary, can you rank the IEMs according to your current preference now?

PS: The Elysian Diva is very hyped and chosen as favourites by multiple reviewers for its vocals by Gizaudio, Precogvision, Shuwaudio, etc. Is it overhyped, or does the vocals truly have an edge over even the UM Multiverse Mentor in your opinion?
As you know, these questions lead to variable, subjective answers. But for my preferences, rough ranking would look like:

-UM Multiverse Mentor (summit-fi presentation with pleasant tonality)
-Oriolus Traillii JP (for wet/organic timbre)
-Elysian X (for top-tier treble and exciting v-shape)
-Aroma Jewel (excellent clarity, clean sound. Could be a bit sterile at times)
-Rhapsodio Supreme Mk2 (for mids)
-Rhapsodio Infinity Mk2 (for energetic upper-mids/exaggerated vocals)
-Erlkonig (fun stage with warm, pleasant mids)
-Indigo (great overall safe bet, just found it boring)

But this ranking can change depending on what tonality and technical preferences you want out of your IEM.

I only briefly heard Diva at Canjam so take it with a large grain of salt but I found Annihilator was a lot more interesting for me. I do not recall Diva's vocals though, would need more time before comfortably commenting on it.


1000+ Head-Fier
The Multiverse of IEMs
Pros: Gorgeous
Fantastic sound
Excellent bass
Great quality mids
Above average treble
High-quality cable
Soundstage/Imaging/Instrument Separation are next to none
Cons: Price
Microphonic cable
Occasionally overwhelming bass
Some sibilance
Less treble presence than some might prefer
MM Front.jpg

Original Logo Small.png


Up for review today is the Unique Melody (UM) Multiverse Mentor Jade/Emerald (MM) Special Edition (the guys who came up with this design call it the Jade, Musicteck, who sells it, calls it the Emerald – no clue what the actual name is.) I was sent this gorgeous piece of art by Musicteck (shop.musicteck.com), who are the only ones I know that carry it, and they are a VERY limited edition (I know of maybe 2 so far.) Anyway, Musicteck sent me these in exchange for a review with a very generous discount, though they were still extremely expensive (Retail is $4,999: https://shop.musicteck.com/products/um-multiverse-mentor?variant=43713129972002.) You pay an extra $500 for the Jade/Emerald edition, but wow is it gorgeous and it actually feels like a more premium product. The stock edition gets some complaints about how the faceplate looks/feels at this price, but it’s still better looking than the *GASP* expensive Oriolus Traillii (especially in red.) As always, receiving a discount doesn’t change how I review since I still had to pay an eye-watering amount for these – I am still my usual critical/sarcastic self.

Anyway, enough about the price and the looks (for now), no one would care about how these looked and the price would be wildly unreasonable if these didn’t have some amazing technology and sound. So, let’s talk about the tech that goes into these and makes them a step above the UM Indigo. The MM includes a new Frequency Shift Piezoelectric Bone Conduction Driver (BCD) – fancy sales-guy speak for palladium-coated copper and ceramic drivers. It creates more stable and structurally sound BC drivers. It’s specifically designed to resonate between 20Hz to 20kHz. On top of that, there are also 1 Balanced Armature Drivers (BA) – 4 bass, 2 mids, 2 mid-high, and 4 high drivers per ear. It’s interesting to see a full complement of BA drivers covering the broad spectrum of sound in addition to one BCD covering that same spectrum. The shells themselves are carbon fiber, which allows them to be both hard and lightweight, oh, and cool looking. So, read on below for why these are my current #1 in my headphone rankings.

MM More Different Box.jpg

Accessories/Earpads/Eartips (8/10):

The MM comes in a plain silver cardboard box that has tiny letters on the side to tell you what’s inside. Inside that box is another blue box which is far more ornate and has some random unrelated art on it (guessing it’s a stock box also since it has a multiverse stick on it as well and no other identifying features.) It’s a bit disappointing that the special edition green MM doesn’t come with a green box – for the extra $500, it should. The accessories inside the bottom jewelry-style box has the usual accessories that the MEST Mk2 also comes with. There are UM tips or Sedna Xelastic tips, filters, a cable wrap, etc. Of course, I’m using my favorite Spinfit W1s to get a great fit/seal (Here if you want a pair.) In the top section, there is a large blue leather carrying case inside a soft white UM bag. Why? No clue, it’s really unnecessary and once again a missed opportunity to include a green leather case with the special edition (booo.)

MM Bag.jpg

The leather case is much nicer than the one that came with the MEST Mk2, but it’s also gigantic for no reason (it’s not as if the IEMs are huge) and when I opened the case, the MM had shifted around in shipping – not something you want from an IEM this price. The cable splitter protector was also protecting nothing and there was only 1 instead of the 2 that the MEST Mk2 comes with (I’ve had 3 now, and I’m becoming an expert on their packaging.) Sooo…yeah, the only upgrade over the MEST Mk2 is a useless soft UM bag that I will never use and a large, pointless leather case in the wrong color (which I imagine is designed to come with the regular blue MM.) Luckily for UM, the MEST Mk2 comes nicely appointed (and with a more useful case), so it's not a massive hit, but they could have done better.

MM Acessories.jpg

Cable (8/10):

Dangit. I was hoping to avoid the cable rant on IEMs this expensive with a custom cable from PW Audio, that has its own name (Deep of Universe Shielding), and would likely retail for over $1,000. It looks like it’s based on the PW Audio Mercer Spider and it’s a shielded 4-core cable with 26AWG copper and silver-plated copper. It’s clearly a better quality cable than most stock cables you’ll see coming with IEMs, and it’s a nice dark green with a green connector and splitter. BUT, and this is a big but (heh), it’s a very microphonic cable. Something at this price should not be microphonic (a pet peeve of mine as I shouldn’t hear a rubbing sound every time I turn my head.)

MM Back.jpg

It amazes me that people still make IEM cables with paracord considering how bad the microphonics are on something like it are. A nice soft rubber here like the Effect Audio EROS in green would have been far more welcome on these. Additionally, it’s a very thick, sturdy cable, which doesn’t have any memory retention, but it can easily get twisted up if you’re not careful as a result. I was thinking the Code 23 in Cyber Green would be a good replacement for this, but they’re sold out, so ah well. Also, it only comes in 4.4mm balanced, so if you can’t use that, it’s not very helpful to you since this cable sort of HAS to go with this IEM – very few people make quality cables in green. Still, it’s good quality and the sound is great, so only a couple of points off for the microphonics as that’s my only real complaint.

MM Box.jpg

Build Quality/Comfort (9/10):

OK, I have to mention some weirdness that occurred for me when I got these. As mentioned in the accessories section, the case didn’t hold onto the right earbud well, so when I opened the case, it wasn’t secured. I looked at the faceplate and saw what looked like divots taken out of the faceplate, so I assumed that the 4.4mm connector had hit the faceplate and damaged it in transit. Understandably, I freaked out, as I mentioned, these were still quite expensive, even with a reviewer discount. Musicteck recommended rubbing the spot with a cloth, which did nothing, and I tried gently scratching it with my fingernail and it came off – I figure it was a little bit of glue left over from manufacturing. Phew, but still not something that should happen on an IEM in this price range (c’mon UM.)

MM Blemish.jpg

After that freakout was resolved, I can say that the build quality on these is fantastic. The transparent green faceplates are awesome looking (being able to see the BCD inside is neat), and the gold trim is very cool when it catches the light (I’m not even a fan of gold stuff.) The green carbon fiber body is excellent and feels very heavy-duty. Quite frankly, they could have made the whole IEM out of this stuff and I’d have been happy. They are very lightweight and feel sturdy as well. I’m not sure how the green faceplate and gold trim will hold up long-term, but I take good care of my stuff, so I should be fine – just avoid knocking them together or putting them down on abrasive materials.

The comfort is good. I don’t find them annoying to my ears and the little shelf near the top of the ear isn’t annoying. They’re a tad bigger than the Noble FoKus Mystique, but quite a bit smaller than the Aroma Thunder and Thieaudio Monarch Mk2. They’re also less thick than the Thunder or FAudio Mezzo LE. So overall, the MM are small-ish, light, good-looking, and well-made (mostly.)


I will be comparing these to the Aroma Audio Thunder as the Thunder is the closest IEM I have in price at $2,600 and it sits at/near the top of my IEM rankings. Below is the Squig.link Frequency Response Graph for both of them. I’m using the bassier version of the switch on the Thunder (I think, it’s hard to tell and there are really no instructions anywhere.) In the Harmony mode, the bass between these two is similar. The mids are also quite similar until you hit 1k where the MM takes a more pronounced approach to the upper mids. In the low-treble the MM dips hard while the Thunder maintains a pretty neutral response until you hit 10k. The MM pops back up after 5k and stays pretty neutral as well until about 11k before the drop. Of course, anything after 8k is typically suspect regardless and anything past 5k is technically outside of the normal instrument range (vocals and pianos cut off after about 3,500Hz and cymbals past 5k.) I burned the MM in for 50+ hours but didn’t notice much of a difference in the sound.

MM Thunder.png

I will be powering both IEMs off of my Shanling M6 Ultra (mid-range DAP king) with the balanced 4.4mm connection (Here if you want one). The MM runs at about 30-34/100 volume level here making them harder to drive than the Mezzo LE and Thunder (28-32/100), but slightly easier than the Monarch Mk2. The MM are definitely not the most efficient IEMs ever, but on balanced just about anything should be able to power them. One thing to keep in mind if you get these is that you need a decent quality source, I tried powering these off my Shanling M3 Ultra (budget DAP king, Here if you want one) and the MM lost a lot of its magic just like the Kublai Khan did – more expensive IEMs need better DAPs.

Lows (18/20):

Starting off with the Mid-bass/Sub-bass test I’m using David Guetta’s “I’m Good (Blue).” The intro bass drums have excellent impact as expected from UM. There’s no bloat or additional unwanted reverb like the Thunder can have a little of on this song. The sub-bass after the intro is strong and clean, with a good amount of that breathtaking quality I look for in this song. So, excellent bass without overwhelming the mid/high synths or vocals. I honestly expect nothing less from UM having listened to several of their IEMs now, but this is top-notch bass, if a little less quantity than the Thunder in Focus mode.

Up next is Demon Hunter’s “I Am A Stone,” which I use to test whether the bass is too strong and overwhelms the mids. While the bass here is quite strong, it doesn’t overwhelm the mids - quite. The mids are still quite easy to hear and they still sound great, but there is a tad too much bass here to the point where it’s distracting. Overall, the bass on these is excellent but will be a bit much for some people on some songs – which is still an issue the Thunder has as well, to an even greater extent. As a quick add-on, the Red Hot Chili Pepper’s “The Zephyr Song” has the same issue – so if you love bass, these are definitely good headphones. Better than the bass on the Thunder, slightly worse than the W900.

Mids (18/20):

Weaving The Fate’s “The Fall” is a test song for guitars and vocals. The clean intro guitars sound good and project a massive soundstage here and good imaging, while the dirty guitars sound really fantastic with the cymbals easily heard in the background. The vocals sound great and appear to be in front of you without sounding too far away like some IEMs. It truly feels like you’re sitting in a club listening to this song – it’s pretty amazing and the bass isn’t overwhelming. The Thunder also sounds fantastic here, but with more distortion, more forward vocals, and almost obnoxiously present treble (this depends on preference.)

Staind’s “Something to Remind You” has clean electric guitars and wonderful vocals – this song tests the vocal quality and background noise. The vocals here are good enough to give me chills, which doesn’t happen very often. The bass guitar is more present than most IEMs, but that’s not a bad thing and the regular guitars sound fantastic with multiple different levels of guitar managing to have their own place without overlapping. Also, while you can hear the fingers moving up the fret on the strings in the background if you listen for it, it’s not as forward and present as it can be on some IEMs – I consider that a good thing since it can be annoying. It’s something that the Thunder makes obvious (somewhat painfully) – also, the vocals are less clean on the Thunder and more distorted (barely.)

To test classical instruments in the mids, I’m using The Piano Guys' “Code Name Vivaldi.” The bass-strings can be a bit overwhelming here, but the mids themselves still come in beautifully. Each note on the piano can be heard, though not as clearly as an IEM with less pronounced bass, especially when the piano hits the lower notes. That said, the soundstage and imaging here along with the instrument separation are fantastic – I am expecting my highs piano test song to sound really good on these based on the performance here. Sadly, the Thunder cannot present this song anywhere near as well as the MM, it’s still great, but it just doesn’t make you feel like you’re there surrounded by instruments.

Highs (15/20):

To test sibilance on headphones I use Panic! At The Disco’s “High Hopes. Yeah, there’s some sibilance on the MM, unfortunately. I’m a little surprised by that as the MM dips around the 3.5kHz range, so I was expecting less sibilance. However, based on how a lot of the highs presentation is on these IEMs, it makes sense that there is some sibilance here. Admittedly, the large majority of headphones I listen to have some sibilance on this song and the MM is nowhere near the worst here, more like the upper middle of the pack – about on par with the Thunder.

The first highs test song I’ll be using is Dream Theater’s “The Alien,” which I use to test and see if the cymbals/high-hats/snare can be clearly heard and distinguished from the rest of the music. The cymbals and hi-hats in the intro can be clearly heard and are quite distinctive. You hear each drumstick hit on them, which puts these into the top tier of headphones with this song. Something like the Blessing 2 will allow you to hear the cymbals, but they’ll just be a muddy mess of sound in the background. Other headphones won’t let you hear the cymbals at all, so the excellent representation from the MM here is impressive and the cymbals manage to not be overwhelming here either – also a win. The Thunder has even more forward treble here, so if that’s your preference, get the Thunder – I find it to be a bit distracting personally. Nonetheless, the Thunder has better treble here.

Michelle McLaughlin’s “Across The Burren” is another of my favorite highs/sharpness test songs as it can easily sound painful on some headphones. As previously mentioned, this seems to be an area where the Mentor excels. There is no sharpness and each note can be heard cleanly and clearly. The notes don’t cut out or distort, which can also easily happen on some IEMs. Perfectly represented. The Thunder have a very annoying hissing noise in the background that is far more apparent than on the MM and they also have more sharpness to the notes than the MM, which is to be expected considering their performance on “The Alien.” Something’s gotta give.

Soundstage/ Instrument Separation/Imaging (10/10):

I use MGMT’s “Time to Pretend” to test soundstage and imaging. Wow, freaking epic. Much better than on the Thunder, which sounds good, but more 2D with everything appearing in front of you compared to the MM. I wasn’t there when they named the MM, but I feel like the crazy ability to envelope you in sound is why they named these the Multiverse Mentor (that, or they just love Dr. Strange.) There is something weirdly magical about the way the MM sounds, that really makes you want to go back and listen to all of your music library again – I think it’s this right here. The MM has an excellent soundstage that doesn’t feel too big, excellent imaging, and excellent instrument separation.


There is no obnoxious driver pop on the MM, which the Thunder has every time you put them in. It’s not the end of the world, but it’s just an additional annoyance, and one I had on the Kublai Khan as well – the MM doesn’t have that issue. The MM also doesn’t have the fit/size issues I’m sure some people have with the Mezzo LE, Kublai Khan, and Thunder since they’re all chonky. As far as sound goes, the Thunder’s bass has more bloat while the mids just aren’t up to the MM’s level, especially on classical. The soundstage, imaging, and instrument separation on the Thunder are a step back as well. The Thunder does however have more treble presence, so if that’s your preference, grab the Thunder and if treble annoys you, avoid it. Keep in mind that the Thunder is fantastic and retails for half the price of the MM – it’s really close for much less $$$. It just can't compete with the MM's bass or mids with that soundstage/imaging/instrument separation.

MM M6U.jpg


The Multiverse Mentor takes the #1 spot on my IEM Ranking list due to its excellent bass, magical mids/soundstage/imaging/separation, solid treble, and its ability to make classical music sound next level without any sharpness. Yes, its treble isn’t as good as the Thunders, and yes, the bass can be a bit much sometimes, but it’s still the best IEM I’ve ever heard, and it matches very closely to my preferences. If you think something sounds better, send it to me to compare. Until then, the Multiverse of Melodies shall continue to be my most listened-to headphone (and the highest-scoring headphone under the v3 scoring chart), IEM or otherwise.

Headphone Scoring (v3):
Accessories / Earpads / Eartips (10/10):
Cable (8/10):
Build Quality/ Design / Comfort (8/10):
Lows (19/20):
Mids (17/20):
Highs (15/20):
Soundstage / Instrument Separation (9/10):
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Did you really have to write this one day before I hit the shops in Singapore???

Agreed on the microphonics and sibilance BUT both can be cured with a cable switch. For me sibilance disappeared after trying a better cable. Of note is that nobody seems to agree on this so YMMV.

UM Multiverse Mentor - The new IEM benchmark?
Pros: - Magical midrange and vocal performance
- Great tonal balance across all frequencies
- Excellent BA bass, in conjunction with the BCD
- Incredible technicalities including speed, resolution, imaging, and layering
- High quality, and ergonomic PW Audio cable
- Comfortable for long listening sessions without fatigue or pressure build-up
Cons: - BA bass (specifically for DD bass fans)
- High cost
- Some slight visual imperfections on the shells
IEM driver technology continues to be one of the most exciting and innovative spaces in the headphone audio market. Over the past few years we’ve seen countless designs utilizing dynamic drivers, balanced armature drivers, piezoelectric drivers, bone conducting drivers, and hybrid designs containing various combinations of the above.

Bone conduction technology is different from the other driver technologies that move air, in that it passes vibrations through the bones in the jaw and skull, directly into the inner ear. In a sense, this means that the sound bypasses the ear structure and the sound is heard from inside the ear, instead of outside.

Guangdong-based Unique Melody are now one of the most well-known manufacturers of IEMs and like many current IEM manufacturers, can trace their roots back to the hearing aid business. They were also one of the first to introduce bone conduction drivers into their products. The Unique Melody MEST and its successor, the MEST MKII were very well received by the Head-Fi community. More recently, Unique Melody continued with various bone conduction designs and had three limited edition flagship products in the Mason Fabled Sound and FS Le Jardin, and the Red Halo, that all used a hybrid design of 12 balanced armature drivers and a full-range bone conduction driver.

The Multiverse Mentor is Unique Melody’s newest flagship product in the Mentor Series and retails for $4,499 for the universal model, and $4,999 for the custom model. During CanJam SoCal 2022, I was fortunate enough to stop by the MusicTeck booth on the Sunday afternoon before the show closed in order to hear the Multiverse Mentor, paired with the fantastic HiBy RS8 digital audio player. It’s always an eye-opening experience when experiencing truly cutting-edge products that are pushing boundaries for the first time, and the MM (and RS8) certainly fell into this category.


According to Unique Melody, the new Mentor features a brand new Frequency Shift Piezoelectric bone conduction driver that was specifically developed for the entire hearing frequency range of human ears. To ensure the driver’s performance, a conductive palladium slurry with high temperature resistance is applied to the vibrators, and a pure copper substrate is added on top of a double-sided ceramic layer. The performance of the driver is also optimized by adjusting the internal structure of the cavity, which also reduces the vibrations sense and increases the comfort.

The Mentor has a 5-way crossover design which features 4 bass, 2 mids, 2 mid-treble, and 4 treble balanced armature drivers along with the bone conduction driver. The Mentor comes with a lovely PW Audio cable with 26AWG copper and silver-plated copper wires. The cable is covered in a soft nylon material, and independent shielding that PW Audio dubs “Deep of Universe''.

I’ve now had a chance to spend several weeks with the Multiverse Mentor and have used it predominantly with the HiBy RS8 DAP, the EarMen Sparrow dongle DAC, as well as with the dCS Lina DAC (set at 2V output), and AMP (set to low gain).

Unboxing and First Impressions
The Mentor ships in a relatively small shrink-wrapped silver outer box. Opening the outer box reveals a silk-screened inner box which opens with a latch system and also contains a shelf of included accessories. The Mentor itself sits inside of the vegan leather case, which itself is wrapped in a white cloth drawstring bag. While the packaging is not what I would consider “luxurious”, it is very professional and imparts an understated feeling of quality.



The accessories include a set of Azla Xelastec ear tips, cleaning materials, and replaceable metal mesh filters. The case, while rather large, is of a high quality and appears to be made by a particularly well-known and popular manufacturer from the Republic of Korea.



Looking at the earpieces themselves, the Multiverse Mentor is made from a Carbon Fiber blue shell, with a Ceramic Frame holding the Bone Conduction Driver, and is finished with a Banksia Seed Faceplate. The Banksia wood in person gives the Mentor a darker brown appearance with splashes of purple that are accentuated when hit with direct light.

The custom-designed cable from PW Audio is a deep blue color that matches the blue ceramic frame of the Mentor almost perfectly. It’s a a 4 wire, 26AWG silver-plated copper cable called “Deep of universe” that is terminated in a 4.4mm balanced pentacon plug. Overall, the cable seems to be of very high quality and while it’s quite large and thick, the ergonomics are very good, with the cable folding/wrapping, and unwrapping nicely.

I found that the relatively small size of the earpieces made for a comfortable and ergonomic fit. Additionally, with a vent in each earpiece shell, there was no perceptible pressure build in my ears, so extended listening sessions were overall very comfortable.


I used the Mentor in three different configurations as follows:
  1. HiBy RS8 R2R DAP, medium gain, Turbo enabled
  2. dCS Lina DAC and AMP, 2V setting, low gain enabled
  3. EarMen Sparrow dongle DAC
My primary configuration was using the HiBy RS8. This DAP has an R2R architecture and is rather smooth sounding while maintaining excellent levels of detail. In order to see how well the Multiverse Mentor could scale, I also used together with the dCS Lina DAC and AMP which added another layer of detail retrieval and transparency while maintaining a perfectly black background. Finally, I used the Mentor with the EarMen Sparrow dongle DAC connected to my Steam Deck for some handheld PC gaming. In both of the latter use cases, 4.4mm adapters were used as needed.

The Multiverse Mentor competes at the highest level of flagship IEM territory and is positioned to take on the likes of the Aroma Jewel, Oriolus Trailli, and other top tier offerings.

Sound Impressions
I’ve been listening to the Mentor almost exclusively for the past several weeks and continue to be deeply impressed. These are among the finest IEM’s I’ve ever experienced and blend a combination of technical mastery and are tuned almost perfectly to my personal listening preferences. Foremost is a great sense of tonal balance across the frequencies along with truly magical midrange. In particular, vocals sound rich and lifelike and have a certain intangible quality that makes them come across as incredibly natural.

While some may lament that BA bass cannot overcome certain shortcomings, I felt that the Mentor’s bass, enhanced by the Bone Conduction Driver, certainly provides a great bass experience with impact and slam when called upon. And while it’s not quite equivalent to dynamic driver bass, I never really thought anything was lacking. Of course, there are also those who prefer BA bass in that it also can be less fatiguing to listen to. As with most things in the hobby, YMMV.

The Multiverse Mentor’s treble is also extremely well tuned. It’s highly resolving and is able to extract the micro details, with the sparkle and shimmer when called upon, but it’s tasteful and never overdone. I’m fairly sensitive to treble sibilance and listening fatigue in general, yet I never felt this while listening to the MM.

The MM is an absolute technical monster. It’s resolution, soundstaging, layering, and overall speed are “best in class” impressive, and are really pushing the boundaries of what’s possible in an IEM today.

Unique Melody has really hit it out of the park with the Multiverse Mentor. While it’s impossible to “crown” a single IEM as being best in its category, I can unequivocally say that it's perhaps the most well balanced IEM I’ve personally experienced, and fits my personal listening preferences to a tee. As an all-arounder with flagship level technicalities, the Multiverse Mentor has a magical midrage, a highly detailed yet non-fatiguing treble, and among the best BA bass I’ve ever heard, aided by the Bone Conduction Driver. Tying it all together is a laser-focused set of technicalities which I’ve rarely experienced in an IEM. The Unique Melody Multiverse Mentor has my highest recommendation and is a must-audition for anyone in the market for a flagship IEM.

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Midrange is definitely magical. One of the top iem you can listen
I wonder what the cost of the drivers and materials is - maybe $500 at most?
Totally agreeing with all the points in the review. The technicalities are out of this world. Usually technicalities mean fatiguing listening to me. But the MM manages to be one of the most technically resolving iem yet remaining easy to listen to. It’s really a “just-one-more-track” kind of iem for me. Homerun for sure!

Scuba Devils

Headphoneus Supremus
Unique Melody 'The Multiverse' Mentor
Pros: > Vast stage with pinpoint layering and imaging: the very definition of a 'holographic' IEM
> Wonderful tuning across the FR, with excellent balance and an overall sense of warmth
> BA bass, as good as I expect is possible without a DD (BCD effect)
> Lush, enveloping mids
> Crisp, airy, highly engaging treble with a perfect amount of 'bite'
> Mid-sized shells are comfortable for long listening sessions, zero pressure build
> Everything you could need in terms of accessories
> High-quality stock cable from PW Audio
Cons: > Shells don't feel quite like a premium look/finish
> Very Occassional spicy upper mids (this might be me...)
> BA bass (subjective, but some might want that indistinguishable DD experience)
> Not cheap...
"The multiverse is a hypothetical group of multiple universes. Together, these universes comprise everything that exists: the entirety of space, time, matter, energy, information, and the physical laws and constants that describe them" Wikipedia

Unique Melody Multiverse Mentor - 12 BA, 1 Bone Conduction Hybrid IEM ($4,499)


Introduction & Caveats

The Multiverse Mentor (MM) is the third set I've now owned from Unique Melody (UM), the previous two no longer with me - first was the infamous MEST MKII which I purchased around it's launch in 2021, and then the MEXT early in 2022, in fact, I think it was my first purchase this year. I enjoyed both of these sets but ultimately moved on as part of the usual cycle of upgrades and exploration. I've been intrigued by various UM releases over the last year or so, quite a few such as the Indigo get a lot of incredibly high praise in the community, and I've been keen to try something that is considered at the level of Traillii or Jewel - which is exactly where MM is positioned. The Mentor arrived on the scene only a couple of months ago, and early impressions from the few trail-blazers that jumped in early were I would say unanimously excellent, a rare feat in this community. I had only recently parted with both Traillii and Jewel, and sort of 'settled' with Kr5 as my only multi-driver set, otherwise having a preference for mostly the humble single DD as a collection focus... alas, curiousity got the better of me, the usual FOMO when hearing all of the gushing praise for Mentor from Head-Fi members who've owned the very best sets on the planet - how could I resist?!

As always, I like to note that I am not a professional reviewer - this is my hobby, and I enjoy trying out various sets and sharing my thoughts. I often get a discount in exchange, but it in no way influences the content of my review - I choose the sets I am keen to try, and this typically means I've done a fair bit of research before pulling the trigger, getting a good sense as to whether it will be a set I will likely enjoy - and for the most part, this has been the case... hence my positive ratings. Some last longer than others, there are only so many I can afford or have the time to hold on to, and part of the enjoyment for me is testing various sets and determining how they compare to my existing collection.

I would like to thank @MusicTeck as always for the opportunity and their industry-leading customer service. Always an absolute pleasure to deal with, and arguably the best audio dealer in the universe... or eh, multiverse.

The UM MM retails for $4,499 and is available from MusicTeck HERE



Unboxing & Accessories

For anyone who has owned a product from Unique Melody already, the overall unboxing experience will be quite familiar, albeit steps up somewhat for this higher-end of the market versus MEST MKII for example, but not a million miles away by any means. I like the UM unboxing, it has a lovely premium feel to it, with a jewellery-like presentation - this has moved up a notch now also with the addition of a soft fabric bag covering the case inside the box, very reminiscent of how some watches are unveiled.

Outer Box: (there is actually a silver outer-outer box, but I decided to omit from these pictures as it's more a protective box)


Under the hood: The aforementioned cloth bag that holds the case... certainly gets the dopamine juices flowing, or maybe that's just me...


The MM in all it's glory, revealed inside it's carry case:


Some words of wisdom from Mr Einstein to ponder before sliding out the tray of accessories:


Contents of the tray, everything you could possibly need to get going with Mentor... (note the few raindrops on the table, my photo-shoot had to then move indoors!)


Accessories laid bare...


The supplied custom stock cable, made by the highly-regarded PW Audio is a 4-count, 26AWG copper and silver-plated cable. This is a shielded cable, with a fabric finish. It looks and feels incredibly premium, and I suspect would be relatively expensive if sold separately. I'm not 100% sure whether there are options on the cable termination, my came by default with 4.4mm and I can't see an option to choose another on the Musicteck product page. It's pretty thick, quite heavy, and does have some microphonics, as such not ideal for moving about the place, or certainly not going for a jog or walk - I don't expect many will have that in-mind anyway for a set at this sort of price point... personally, the ergonomics of the cable in this case are not an issue, as I'm typically seated when enjoying MM, or indeed any sets at this sort of level. I appreciate that many have their favourite cables anyway, and might skip the stock altogether - it must be noted though that this is a premium cable, and significantly better than some competitors at this level.



The faux-leather case is made by a 'well-known' South Korean manufacturer, probably no prizes for guessing but I'll stop short of listing anything here, as I don't know for sure. It is indeed a high-quality case however, and is certainly of a size to comfortably hold MM and the relatively thick PW cable.



The supplied tips will again be familiar to anyone who has owned another product from UM, the stock silicone and 3rd party 'Xelastec' from SednaEarfit seem to be the standard with any UM product, and should certainly provide an option for most ears out of the box, in the very unlikely event you don't have a selection of others to choose from.


Design & Fit


According to UM, the shells are made from aviation-grade carbon fibre - they are smooth to the touch, reasonably small, and presumably quite robust due to the materials used. The shells are nice, and they do feel well built - a nitpick, but I do feel they could up their game somewhat in terms of the overall finish, they don't quite hit the mark for me as a $4.5K IEM.

They are terminated with a slightly recessed 2-pin connection, and the stock cable feels very secure. There is a small vent to ensure no pressure build, something I am very prone to and thankfully have had no issues to report here, and an absolute deal-breaker now if any set causes even a small amount of pressure.

From a fit perspective, they sit very comfortably in my ears. I've been using the SednaEarfit Azla Short Standard variety as opposed to any of the included tips. I struggle with shells that are even somewhat large, and I was nervous than Mentor might be an issue - thankfully not the case, but I think even slightly bigger and they may have been a problem. I've had many extended listening sessions (>two hours), and have had zero fatigue.


Listening Impressions

I've been listening to Mentor on a few different sources, and I'm finding great synergy with all of them - my favourite however is probably the latest addition to the collection, the excellent H7 from Shanling which just arrived with me a few days ago. The H7 strikes an excellent balance in terms of a clear, somewhat neutral sounding source that still drives huge power into the lows. Aside from the H7, I've had many hours on both the LPGT and Shanling M9, both offering a different perspective on the same set, with M9 as one might expect driving more emphasis to the lows, while LPGT of a more neutral variety.


MM are the single most impressive set I have had the pleasure of trying on my IEM journey to date: exquisitely balanced across the frequency range; wonderful deep lows, lush/engaging mids, and super crisp treble, all wrapped up in a set that has what I would consider to be a unique blend of technical mastery and summit-level engagement factor; a tricky feat to achieve. They comfortably tick that 'all-rounder' box for me, in that they often knock the ball out of the park with ease for absolutely any genre I've tested... however, they are of course better with some genres than others - personally, I would be more inclined to load up various sub-genres of electronic music with MM, and less inclined to choose something such as modern classical - the reason being, I do prefer dynamic drivers from a timbre perspective when it comes to instruments such as piano or strings, both of which often feature in modern classical music. But again, I must note this is quite marginal: I will happily listen to modern classical on Mentor, and thoroughly enjoy - just my preference when owning multiple sets would be to grab something like the Turii Ti in those scenarios.


I hate to use the 'for a BA' descriptor, but I feel it's appropriate - so here it goes: Mentor has the best bass 'for a BA' that I've heard. Mid bass has excellent impact and feels incredibly defined, I honestly would be hard pressed to distinguish at times from a dynamic driver if tested in a blindfolded listening scenario - genres such as techno, house, IDM to name a few of my favourites in electronic often call for solid mid bass delivery and I've been constantly amazed when firing up these portions of my library: there is often even almost a sense of air or vibration that one would expect from a DD, presumably this is due to the bone conduction, which certainly delivers. There is a bit of a bias towards mid bass over sub, but those lower registers still certainly convey a wonderfully visceral experience when called for, and I think again overall, it strikes an excellent or maybe even perfect balance - I don't get a sense of mid bass overpowering sub, or vice versa - they are wonderfully distinct and respectful to one another, and indeed form a solid foundation for the unique soundstage, which I'll come to later.

A critical element to an emotive & engaging listening experience are how the mids are rendered - In my experience, I would say a few key components must be achieved: smooth, clear, unimpeded with good body, realism, and a touch of warmth - MM as one might expect at this level, ticks all of these boxes, and probably many more that I've not listed here. Vocals and instruments are beautifully rendered, and really do enrapture with a unique sense of delivery, again this seems to be that secret sauce of bone conduction magic... it provides a core foundation to the entire listening experience, that really is like no other. Again, this should go without saying at this level but I'll note none-the-less; there is zero congestion, the most complex of passages in an absolutely any track I've listened to, always have ample space and speed for each component, more often than not actually amazing me as to how the heck an IEM can position from an imaging perspective with such a vast sense of location on stage. There can be a touch of spice in the upper mids in some very rare scenarios, so rare I can't even pinpoint where it has happened and it might be a sensitivity in that area I've flagged in the past.

As I learn more about how IEMs perform, and indeed what my own preferences are, I've got a better handle on the crucial role treble plays in a finely tuned set: too little can result in a set that steps back from a technical perspective, especially in micro details - and indeed the higher registers of instruments or vocals can fail to reach the soaring heights they might otherwise... too much, and there is a risk of the dreaded sibilant vocals, or harsh/piercing tones that scream all the way into the depths of your skull. A good balance is often just on the cusp of being too much, and I guess this is easier to achieve when you've numerous drivers delivering the goods, as is the case here with Mentor, and needless to say UM have certainly tuned just below this tipping point. There is ample zing at the upper end to provide a good crisp delivery of hi-hats and allow instruments soar to the upper extremities, but stop short of any discomfort.

There is a unique soundstage with BCD the foundation that seems to allow sound to emanate outwards from a central point in my head, to what feels almost infinite distances - of course it ends, but I find a sense of vastness that is almost hard to pinpoint, I guess this is where UM were coming from in the context of ‘Multiverse’, it feels like a well chosen name. While it’s not especially airy, it has more of a binding warmth that still allows what I consider industry-leading imaging and layering in a very distinctive and cohesive atmosphere - it has the charm of Traillii, with near enough the technical prowess of Jewel, and for my ears at least, beats both in terms of the overall package. Detail retrieval from the absolute smallest, to the biggest and boldest, is there in abundance but again, delivered in a cohesive presentation.



Vector Lovers - Melodies & Memory (IDM / Downtempo / Electro)

This track features on the excellent 'Capsule for One' reissue, originally released in 2005 on the legendary Soma label. This falls under the downtempo / IDM / electro umbrella, and for me, is about as good as it gets when played on Mentor. I mentioned above how the bass is wonderfully balanced between sub and mid, and this is absolutely evident in this track - the mid bass kicks with massive authority, and the sub rolls adjacently, in touching distance but comfortably apart. The synths are beautifully rendered, and seem to soar across the stage as they emerge and fade away - the vocals sit centre stage, and for my ears, in a perfect position that doesn't push too far forward or back.

Jane Weaver - Heartflow (Psychedelic rock, female vocals)

This is a great example of a track made with 'real' instruments, and I don't have any issue with timbre - it's a busy, lively, energetic track and Mentor as you would expect, has absolutely no issues with numerous instruments and vocals charging to the fore - in spite of the complexity, it's very easy to still pinpoint individual instruments and at the same time, enjoy the full performance. Jane's vocals are again as above, in a perfect sweet spot for me where they are in line with the music; not forward or back and quite central. Vocals certainly a huge strong point with Mentor, I'm not sure whether the BCD can take any credit here, but I expect it's playing a role along with the BAs for the mids. I've noted previously how I prefer Turii Ti for some instruments, but it does tend to be within the more relaxed genres where there is more of a specific focus on an individual instrument, this is not the case for this track, and indeed many others like it.

Ceephax - Telephax (IDM, Acid, Ambient, Techno)

A recent purchase, and likely a late entry to my favourite albums of 2022. Ceephax records also as Ceephax Acid Crew, which is a nod towards late 80s / early 90s acid house - I've never been to his gigs, but they certainly look fantastic from what I've seen on YouTube. His recordings as Ceephax are more towards the subdued, melodic side of electro/techno, and this latest album is certainly a fantastic example. It's again a genre that really excels on Mentor, I find a genre like this is best presented when bass, through mids and treble are well represented, and you can get that sense of deep bass, lush mids, and crisp treble to truly appreciate the full production. There is often quite a lot of intimate details in these tracks, that can be lost in some sets - every single detail of 'Telephax' is presented in it's full glory, and is a wonderfully encapsulating experience. While listening to type up my thoughts, I just wanted to hit repeat and go again, a fantastic track from an extraordinary album.

Akuratyde - Evergreen (Electronic / D&B)

I always, without exception test D&B on an IEM - it's a great genre to test how a set handles the complex drum programming, that can easily become harsh or congested due to the frequent snare and hi-hat hits - not to mention the need to ensure it can dig deep enough to render the sub bass well, a signature of the genre, as the name 'drum and bass' suggests. No surprises here, Mentor scores top marks for this excellent track - a big and bold presentation, with complex percussion handled with absolute ease. The melodic synths seem to float about in unison with the drum programming, and it is again an incredibly captivating experience. I will certainly file D&B under the Mentor banner for future listening.

T.R. Jordan - Encoder Error (Electronic / Ambient)

This is not only one of my favourite albums from 2022, but already what I would consider an ambient classic. I have played countless times since I purchased early this year, and it's often an album I choose when I can't sleep, something that happens all too often these days. Anyway, I know the album intimately well, and am reasonably fussy about how I hear it. Mentor does a very good job, but I would say falls a little short of excellence - this is where Turii Ti steps in for me, I prefer the more 'gentle' tuning, the airy presentation, which for me is more natural and organic sounding for this genre. Don't get me wrong, I could absolutely happily enjoy/love/adore this album on Mentor, but I'd be less likely to reach for this set for this music while Turii Ti is in reach.

Symbolico - Gaian Portal

This is a work of production genius, and an ideal track to test the technical capabilities of a set - and indeed to experience an utterly visceral experience when the right drivers are plugged into your ears. Again, we are back in a territory here where Mentor shines, an absolutely perfect set to capture all of the intricate details that spread out across the huge stage, new sounds presenting themselves, while others fade out into the distance, climatic moments that likely have every single driver in Mentor firing on all cylinders, and proving the technical prowess of tuning achieved here. It's honestly a fascinating, and highly engaging experience to hear this track on a well tuned IEM, and Mentor is as good as it gets in my experience.


Oriolus Traillii
While I no longer own, I am going to attempt a brief high-level comparison with the legendary Traillii from Oriolus. I adored Traillii, however that comes with two key caveats: the first being pressure build, and the second being the need for 'focus time' for me to properly enjoy, something I often noted when sharing impressions when I owned the bird. Traillii was a more gentle listen, I think more of a relaxed and smooth finesse to the tuning - it was because of this, I always had to focus my attention to really appreciate the tuning. Traillii has a bit more extension in the sub bass, while steps back in mid bass - Mentor certainly packs much more of a punch here, there was no mistaking the fact that Traillii is 'only' a BA driving the bass. Overall, Mentor is certainly a more energetic set. If it wasn't for the pressure issue that presented itself from time to time, I probably would have held on to Traillii for those magic moments of focused listening, it's certainly a complementary set to Mentor for those that can own both.


Softears Turii Ti
Mentor is in general much more impactful in it's tuning; the notes are larger across a much larger space, as such it grabs your attention in a more macro way - quantity of low-end is significantly enhanced, and lends itself above Turii Ti in general to more energetic genres - Turii has a more graceful tuning, an airiness that is somewhat gentle and in my experience, instruments such as strings or piano sound more authentic and ethereal. While Mentor can comfortably play strings, and do so very well, I would certainly choose Turii Ti for this type of music as I feel the weight and density of notes are excessive in comparion when I play on Mentor, Turii Ti is more visceral for genres that focus on strings, vocals, acoustic etc. Either set can play any genre, and Mentor on the whole a stronger all-rounder, but Turii Ti has it's superpowers in my opinion from a timbre perspective with specific instruments or genres. Taking a genre like Modern Classical, Mentor will 'wow' you with the vast stage, and stunning imaging and layering - Turii Ti steps back in that regard, but for me at least, wins the timbre prize, and becomes a lot more emotionally engaging as a result.



The Unique Melody 'Multiverse' Mentor is without question the most impressive, and I would say 'best' IEM I've heard - it comfortably surpasses both Jewel and Traillii by quite a margin, combining a superb blend of sheer listening engagement, and world-class technical mastery. It's hard to label an IEM as 'perfect', because that is quite a statement, but I feel inclined to say it's certainly incredibly close in terms of at least some of my listening preferences - maybe a DD for bass, maybe some timbre improvements, and maybe remove those brief upper mid challenges that pop up on a rare occassion, that might just allow me to say Mentor is perfect - but on the flip side, these changes will have a knock-on affect, and Mentor would no longer be what Mentor is today - an exceptional set, that delivers on a vast amount of fronts, and absolutely earns a seat at the table of the best IEMs on the planet, or indeed the multiverse...



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About the bass, competitive with the fir Kr5 ? 😉

And nice review 😎👍
Scuba Devils
Scuba Devils
@DaveStarWalker - it’s reasonably competitive, but KR5 takes the prize for me due to the dynamic driver. KR5 remains my top choice for a hybrid IEM at the moment, fantastic IEM.
Ok thanks. Very interesting bro.


1000+ Head-Fier
Unique Melody Multiverse Mentor Review
Pros: - Beautiful vocals and strings
- Bone Conductor Effect
- Good quality cable bundled
- Great fit (for me!)
Cons: - Various face plate finishes in the wild
- Cost



Unique Melody gave me my first introduction to bone conductor drivers in the Mest Mki. It added a little bit of magic to that set and was something I immediately connected with. Since then I have always had at least one set in my collection that has a BCD. While I’ve kept clear of the ultra-expensive models UM has released over the last while, very positive initial impressions from the community were enough to draw me back in and pick up Unique Melody’s latest set from Andrew in MusicTeck.

The Unique Melody Multiverse Mentor, to give it its full name, is a 12 BA & 1 BCD set. There are 4 BA looking after bass, 2 for Mids, 2 for Mid Treble and 2 for Treble along with the piezoelectric “frequency shift” bone conductor driver.

The shells are made from carbon fibre with ceramic frames and a “Banksia Seed” face plate. The IEMs have a recessed 2-pin socket and come with a high-quality cable from PW Audio with a similarly interesting name, “Deep of Universe”.

The shells are a standard hybrid shape and size. I have had no fit issues at all with them. I have been using SpinFit W1 tips with them and once inserted, they stay put and I never need to readjust them.

As you will see from the images I took, there seems to be a range of different face plate colours out there. The unit I have is quite dark compared to the product shots but I have seen others that are somewhere in between.

I’ve been listening to the Multiverse Mentor for the last few weeks and these are my resulting impressions. I am only one voice so please treat these impressions as such and remember that we all hear differently!

What’s in the Box​


The packaging Mentor comes in is good quality and an improvement over my previous experiences with UM. The cardboard is good quality and the tiered box is well put together.


The Dignis vegan leather carry case is presented in a white dust cover which you would usually associate with high-end jewellery or handbags so you get an idea of what UM are aiming for.


The carry case is very soft to touch and feels good in the hand. I am not sure how the softer material would stand up to rough and tumble of commuting in a laptop bag, but it is certainly a nice case to keep the IEMs in on your desk.


UM includes two different types of tips in a number of sizes along with a warranty card and a cable clamp.


Mentor has a fairly natural tuning which is very easy to listen to. Bass is elevated and is assisted by the magic the BCD adds.

I often find it hard to describe the effect a bone conductor has on the overall sound of an IEM. Graphs just don’t tell the full story and that is definitely the case here with Mentor. The vibrations from the BCD give a tactile feeling to drum strikes and strings being plucked while the Mids have a body and presence to them that you just don’t find in sets without this type of driver. The combination of details, clarity and that presence that the BCD brings add up to a very interesting listening experience.

That BCD also helps to create a 3D soundstage with excellent imaging, layering and separation. The size of that stage varies with source but the sense of having music coming from all angles or spaces around you is present even with weaker sources. The ability of the set to build a picture in your head of where each instrument is located within the stage is impressive and combined with the level of detail, it adds to that sense of “being there” rather than just listening to a recording. I really feel the BCD has a big impact on the overall listening experience. It takes good tuning and adds an extra level of engagement, and for me, it is why Mentor stands out from many other sets.


There is a certain familiarity and nostalgia attached to dynamic drivers. Most of us grew up listening to speakers which had dynamic drivers and when it comes to bass the air movement generated by these types of drivers has a very distinguishable effect. For some, BA drivers will never be able to recreate bass how they want but the introduction of bone conductor drivers I would suggest has changed that reality somewhat. If you can’t get past a set not having a dynamic driver to generate bass frequencies then there is little I am going to write here that will change your mind but I would suggest you open it and explore what sets like Mentor can now offer.

We all have test tracks we like to play to test the different aspects of bass. For me, many of these tracks have drum solos or detailed isolated drum strikes that allow you to follow from initial contact with the drum skin right to the end of the decay. If I play one of these tracks back to back on Mentor and on a dynamic driver set then it’s easy to pick out how the dynamic driver sounds more true to life and how the texture and decay just sounds more familiar.

During all my casual listening with Mentor though, it has been incredibly rare that I have even noticed what type of driver is generating the bass. You don’t notice unless you go looking for specifics that you know the BA drivers can’t produce when compared to a dynamic driver. Sure, you don’t get the same sense of air movement, but you do get impact that isn’t lacking, along with the vibrations the BCD is creating and as an overall package, the bass quality is excellent.

While the BA characteristic of speed is there, the timbre is a hybrid due to the BCD effect and something you have to experience to fully understand. There is a sense of rumble far beyond what I have experienced in any other BA-only set.

The simple fact here is that Mentor creates a better bass experience with the drivers it has than many lesser dynamic driver sets and I think for a lot of people this set will change their preconceptions about BA bass.


Note weight, details, and clarity. All stand-out aspects of the mid-range of Mentor. Mids sound beautifully natural and accurate but there is a combination of details and body to them that is unique.

Vocals and stringed instruments are exceptional. There is a fine balance between warmth and detail with neither ever allowing the other to ever take over. Sometimes sets that have so much detail and resolution on offer can lean cold or lack a little emotion but Mentor balances it beautifully. Vocals are life like, crystal clear and importantly for me, connect with you.

There were times during my testing when I came across tracks which I found to be a little too energetic for my tastes in the upper mids but after extensive tip, cable and source rolling that has come down to the stock cable for me, but this, of course, is all down to personal tastes and not an issue with the set itself. With the stock cable there can be a little more bite or crispness in the upper mids compared with other cable combinations, which I will go into further below.

I listen to quite a lot of acoustic music which has just a couple of instruments and a singer and for genres such as this, where the mid-range is so important, Mentor is fantastic. It allows you hear and appreciate every detail but there is more to the overall experience than just hearing details and I think this is where the BCD really elevates things. The sense of feeling it adds along with a soundstage that gives that sense of being at the venue or in the recording studio with the artist, creates a listening experience that is unique.


The BA treble of Mentor is clear, detailed and extends well. It is easy to listen to and has never become fatiguing. It doesn’t have the great sense of air or shimmer that piezo or EST drivers can create but it also has non of the problems that often accompany those drivers. The Treble is in line with the overall tuning and is capable of handling pretty much any genre. While there are no party tricks here, having well-tuned treble that can handle various types of music is very welcome and something that many sets just don’t get right. Treble is one of the last things on my priority list when assessing a set but often the first to rule a set out.

This really is BA treble done excellently. There are no spikes or harshness and everything is incredibly detailed and natural.


The Multiverse Mentor is an expensive set of IEMs. As a result, I have specifically picked tracks and equipment set ups that I know bring the best out of the set I am comparing Mentor against so hopefully people can get a an idea of whether the outlay is worth it for them or not.


Noble Kublai Khan​

Kublai Khan is an impressively technical set for its price and if it clicks with you, it can be a very rewarding set to own. It is definitely not a “one and done” type set though. It has strengths from its driver config that certain types of music really bring out.

Trøllabundin by Eivør

Listening was done with a Hifiman EF400 in Low Gain OS, which suited both sets more than NOS.

I am not sure what genre this track exactly fits into but Kublai Khan is suited to it perfectly. The track is mainly focused on the singer’s vocals, which are captivating, along with a drum beat accompanying her throughout. With the right gear, the track has a sense of grandeur, like you are listening to the singer perform in a huge open space. Bone conductors really help to amplify this and I have often felt this track sounded quite flat when I listened to it on sets without them.

With Kublai Khan, the drum beat in the opening seconds like it is in the room with you but your attention is then quickly drawn to the singer’s voice and rarely leaves it after that. The vocals are smooth and almost have an ethereal feeling to them from the piezo tweeter when the singer hits the higher notes.

As the track opens up, the sound stage becomes huge but your focus remains on the singer’s voice.

Swapping to Mentor, the first thing I looked for was how the opening drum beat compared. For sure, with Mentor there is less intensity to each strike. You lose some of that feeling of each strike that DD texture brings to the table. What you don’t lose though is quality. Everything sounds exactly like it should.

Where the differences in these sets really shows is the body and weight of the vocals. With Mentor, the vocals are more detailed, grander, and carry more weight but yet come across as smoother than with Kublai Khan which when compared back to back with Mentor has some sharp edges.

For this track, the drums definitely go to Kublai Khan but for where it counts in vocals Mentor produces a more enthralling experience.

Stupid Girl by Garbage


This is one of my favourite tracks to listen to with Kublai Khan. It does an excellent job of clearly separating all the different instruments and the vocals so it’s easy to hear them all. Nothing is overpowered and as the track gets busier you don’t feel overwhelmed or like many sounds are blending into one, which happens with many lesser sets. Vocals and instruments are all positioned equally and it is a very enjoyable listen.

Swapping to Mentor, there’s some noticeable differences in dynamic range and note weight. The bass line is more prominent, as are the drum strikes. The different sounds and effects that come into the track are positioned in a more 3D space and their intensity grabs your attention. There’s noticeably more details and clarity in the vocals but at the same volume levels as Kublai Khan, it is a more intense listen.

When I swap back to Kublai Khan again, the difference in details is immediately noticeable but it is a smoother listen so it will be a toss up between which you value more to pick a winner between them on this track. Personally, I would lean towards Kublai Khan.

Interestingly between the two sets, it is not BA vs DD bass that dominates the comparisons. Both do bass very well and are helped out with BCD drivers. In all my listening comparing them, the differences in treble was something I spent a lot more time comparing to decide which I preferred. With all that said though, the superior mid-range and details on offer from Mentor stand out.


Softears Turii Ti​

This was an interesting battle for me. A politely tuned singe dynamic driver versus an all BA set with the big question being what does the BCD in Mentor bring to the table.

Take the Power Back by Rage Against the Machine.

Cayin N8ii Tubes/P+/AB/Low Gain


Like most tracks on this album, Take the Power Back is aggressive and hard-hitting. It’s a busy track and what I am mainly looking out for is how easy it is to clearly hear each instrument, the vocals and if it’s a coherent listen amongst so much intensity.

With Turii Ti, the intro sounds excellent. The drums and bass guitar are accurate and sound great. As the vocals come in they are clear and easy to distinguish. As the electric guitars enters in stereo, it completes a soundstage that wraps in shape from one ear to the other. There is nice positioning and separation but the soundstage isn’t huge and as the track intensifies, that leaves a lot of sound focused in what feels like a small area. Turii Ti handles it well though and once you keep the volume at reasonable levels the whole track is presented well.

Swapping to Mentor, I initially thought the first stand-out difference would be the bass drums strikes in the intro followed by the opening bass guitar line but that wasn’t the case. Turii Ti probably sounds a little more life-like in its reproduction of these two instruments but Mentor has more impact and weight to the notes and you would be forgiven for thinking this was the DD set.

The soundstage stretches slightly further left and right with Mentor but the depth is about the same.

There are two clear differences between Mentor and Turii Ti here though. First is the difference in detail. With Mentor, all of the instruments sound fuller and each note is more detailed and more clearly defined in its space. It leads to a more intense listen but the details are there to support that and even the more delicate cymbal hits in the background are clearly identifiable. The other difference is that vocals are slightly more forward and as there is more detail it makes them easier to hear.

Turii Ti has a slight edge for accuracy which is more evident in the intro when you can just hear the bass drum followed by the bass guitar but as the track gets busier, it is the superior details of Mentor that stand out again.

Seven Nation Army by the White Stripes

Mentor: Cayin N8ii Tubes/P+/AB/Low Gain

Turii Ti: Cayin N8ii SS/P+/AB/Mid Gain


Interestingly for this track, I had to use different settings on the N8ii to achieve a sound from both that I could compare. Maintaining the same settings as the previous track left Turii Ti sounding a little too smooth and rounded for a track that needs a little grit.

So, to a track that probably has one of the most recognisable drum and bass riffs of any song.

Listening first on Mentor, it is clear what effect the BCD is having from the off. The opening bass line has grit and vibration to it. Vibration that you feel in your head and in the seat of your pants. There’s a satisfying thud from the bass drum and the vocals are superb. Detailed, clear and never overpowered by the instruments.

Like with the previous track, the technical aspects are excellent. Everything has its own clearly defined space within the soundstage and everything is detailed and textured.

Swapping to Turii Ti, even with the more aggressive settings on N8ii, the opening bass line is still smoother than Mentor and while there is the sense of feeling the vibrations it is not as intense. Concentrating on the bass drum strikes, Turii Ti is more true to life. There is a realistic texture to the bass drum hits that sound a little 2D in comparison on Mentor but there isn’t as much impact with Turii Ti.

Ultimately it comes down to a choice between the slightly more accurate Turii Ti or the more detailed and more intense presentation of Mentor. I can happily listen to the track on both sets but I would lean towards preferring the track with Mentor as it has a little more bite which suits the track.



The cable Mentor comes with reassembles a non-shielded First Times but it feels slightly lighter and I much prefer the hardware. According to the MusicTeck website, the cable has 4 independently insulated cores which are a copper and silver-plated copper mix. Overall I have been quite happy with the cable. It’s detailed and very accurate but as I mentioned above there were a few occasions when I thought there was a little too much upper-mid energy in some tracks. Whether that is an issue for you will be down to your own preferences and no doubt hearing.


Liquid Links Venom​

Listening to Come Together by The Beatles, the differences are minimal between these two cables. There is slightly more air with Venom but with the original cable there are more details.

Bass is slightly more boomy with Venom but the increased sense of air gives notes further to travel so it does sound a little more closed in when you swap back. There’s no clear reason to see Venom as being an upgrade here vs the stock cable.


Khanyayo 4W Cardas Clear Cable​

This was a much harder one to call at first and it took a lot of listening rather than going back and forth between cables to appreciate. One first listen with the Khanyayo my reaction was “wow”. The dimensions of the stage were pushed out and it wrapped further around your head. There is a little more clarity and warmth to the vocals which I really liked but they are also somewhat darker. This is noticeable when swapping back and forth with the stock cable but not something you notice after some brain burn-in.

Bass impact increases, becomes a little slower but it can also be a little loose sometimes. It doesn’t sound as pristine or pinpoint as with the stock cable but the sounds appearing out of a black space in a larger stage grab your attention.

The pros of the cardas clear copper cable are a richer, warmer mid-range, more bass and a bigger BCD effect but this comes at the cost of accuracy and at times looser bass.

I look forward to trying different cables with Mentor as it is the type of set that you should be able to really fine-tune to your exact preferences with a little experimentation.


It has been a really enjoyable journey with Mentor so far. Getting used to what it can offer, matching it with different sources and cables and importantly finding a new way to enjoy my library has kept me excited and wanting to come back for more. Always a sign of a great set.

Note weight, details, clarity and a BCD that adds to the experience on so many levels combined with an ability to cover just about any genre makes the Unique Melody Multiverse Mentor an easy recommendation for anyone to try. It is excellent technically but also an engaging set that sucks you in and keeps you listening to “just one more track”!
Great review bro!
Great review! Looks like you got a good looking set of face plates!
Great review 😎👍