Unique Melody Mason Fabled Sound Special Edition


100+ Head-Fier
The Beauty for the Beasts
Pros: Detail Monster
Instruments separation
BCD latest generation for great slam
Stunning Visual
Cons: Cost, unless you wanted to buy this PW cable anyway
BCD requires a good fit with UIEM, Custom is preferred
Shielded cable ergonomic is not for everyone
The name...

Few words about my taste so you understand my bias:
I am a Traillii lover, I like the neutral, smooth, airy sound with great respect for the vocals.
But I have always got a nice affinity for the UM brand. Lately, the MEST Indigo is one of my favorite IEM.
That's why I used both these IEMs to compare the UM FS LeJardin.
(I love the Fir Audio Xe6, but it is a bass oriented set that is not playing in the same category)

I did not check any review, any FR graph before I wrote the following, to share my impressions with minimum influence.
It is a very expensive set yes, and this review is not here to answer if it is a good value/price item. I would consider this item a piece of jewelry or luxury accessory.
The build quality is the one you could expect from an expensive set.


Lovely box, lovely leather case, however way to big to be considered a transport case. I wish more brands would include some Van Nuys carrying pouch. Things that are actually useful!

Review is not my thing
So we are clear: I am terrible are reviews. I probably don't have the earing capacity for specific details or the memory to compare both sound signature with accuracy.
Moreover, lately I had trouble to make up my mind if I prefer or not an item when doing A/B testing. (Sony M2, now the UM FS)
That's why I took time to publish that, cause I changed my mind a crazy amount of time.

Non SQ stuff

I guess we can't talk about the UM LeJardin without mentioning how gorgeous they are. The first thing I did when receiving them has been to take pictures


They look good from every angles, whatever the light, they are just the most beautiful IEM I own.


Unlike the UM Mest Indigo which feels fragile, or the Xe6 UIEM that get scratches super easy, this IEM feels solid. doesn't show fingerprint, or anything.
I would still not carry it in my jeans pocket without protection.

They are larger than the Traillii or the Indigo. Not as big as the EE EVO / Odin.
They are slightly bigger than the Elysian X.


From left to right: UM Mest Indigo, Oriolus Traillii, FirAudio Xe6, Elysian X, UM LeJardin

Fit and BCD
Finding the right eartips is the challenge. As recommended by friends, I went with smaller Eartips size than usual and it did the trick.
While I went away from the Xelastec at first, I went back to it after many tip rolling. But I indeed took 1 size smaller than usual and it really helped to feel the BCD.
They are a bit bigger than I like. (Traillii, MEST, Xe6 are perfect to me)

Speaking of the BCD:
It is really an improved version, nothing alike the MEST mk2 or even the Mest Indigo. (or the EE EVO)
It is a good and bad thing! Cause depending how well the IEM is positioned, it really changes the song. I would definitely suggest CIEM if you go for such a purchase to get the full experience. It is my only regret with this UIEM, I feel like sometime I don't get the best out of this BCD. It is the first time a BCD is really making a difference for me.


The cable


I already own a shielded PW First Times, so this cable was not really a discovery. I did not do proper comparison of the two, but they do sound similar. Most important: They have the same ergonomic. You love or hate it.
Very stiff, lot of memory after the splitter, and it takes more space than any 8 wires cable I own.
Disclosure: I am an EA Centurion fan.
However, the PW FT is on my Traillii at the moment.

Surprisingly, I switched the PW MeetAgains for the Centurion as it felt too warm to my taste. I felt that the Centurion has been helping on the vocal and treble.
However, after a week, I went back to the stock cable and kept it. I feel it gives the bass it is supposed to and a nice organic feels with some instruments.

It is a nice cable, if you don't own an Orpheus or FT, it is something to have in your TOTL collection.
No Microphonics at all with the shielded version.

So, how does it sound?

I did the usual and went through songs I know well and compare with Traillii and Indigo.
However, the conclusion was always the same, so I will go quickly over it:

While the Bird will sound brighter with more focus on her voice, the UM will have a better slam, better drum, claps.

The Bird has a bigger soundstage, but it is more than that, the positioning of the instrument feels really different between the two.
The UM LeJardin feels as if most of the sound are lined up in front of you, but you can really feel some instruments in the top left/right corners, maybe due to the BCD. It is the first time I can locate sounds this much in the corners.
With the Bird, I feel in the middle of the instruments, with a lot of space between.

The UM Indigo is more V shaped, with stronger bass presence and yet forward vocals. It is where the A/B testing makes it difficult for the UM LeJardin as it is a more neutral set.
The UM Indigo is more engaging on this song. However UM LeJardin is better with Guitars, more sparkling sounds, but it is more linear than the UM Indigo.

From this song, I started to realize how great the UM Lejardin is at instrument and vocal separation. It is a detail monster as well that is less forgiving with bad recording.
This song unfortunately was better with the UM Indigo, as some details of the recording are not showing up.
I started to see the technicality superiority of the UM LeJardin from here. That said... the song is more enjoyable with the UM Indigo!

On the Indigo, more bass but less textures compared to the LeJardin.
The Bass are too dominant with the Indigo, I definitely preferred the song's presentation with the LeJardin.
The Traillii is very similar to the LeJardin, but more open and less slam. I could repeat this statement for all songs between these two.
Probably cause I listened to this song 400 times with the Bird, my preference goes to it, but the LeJardin is excellent and right behind.

Same old... Brighter with the Bird, more open. More bass and slam with the UM Lejardin, very enjoyable with both.
I compared way more songs but the conclusion is the same.

About the source

Most of the listening and the comparison have been conducted with the N8ii, ssd setting, P+, High Gain.
I tried it with multiple sources, this set likes power. I could plug it to a desktop amp and have a nice sound, similar to the Elysian X. It scales well, but the N8ii was more than enough.
It paired very well with the Fiio K9pro (the AK version)
With the Ifi Go Bar, Xbass and Xspace settings, it sounds awesome. Since I paired them, I am no more using the N8ii for the UM Lejardin. Surprisingly, you must use the IEM Match, then increase the volume to get the best potential.

So What?

I went through many emotions while evaluating this set.
Loved it, had moments of regrets due to the price, I wondered if it was this good, etc...

I brought it outside for a full day, and it is how I fell in love with it. No more A/B testing, just enjoying the sound. It took more time for brain burning than other sets.
It is a detail monster and great at instrument separation, I enjoy to hear some choir or side voices more clearly on many songs. The bass are definitely better than the Traillii, so it helps enjoying a larger library.

I will probably change my mind in the future, but for now, it is my main set. I still enjoy the Traillii, but I feel like I miss something compared to the UM LeJardin.
If I want to go Electro, I can use my bass canon Xe6, but for the rest, the UM LeJardin is a great choice.

It is a beautiful set, a beautiful sound.



Headphoneus Supremus
Pros: Bone Conduction Driver, unique sound qualities, astonishing sound reproduction, technical performance, musicality
Cons: price, cable a bit stiff and heavy, packaging and accessories (comparatively speaking)

Unique Melody will by now need little introduction from me, since they’re not only a very well-known and established company from China, but also one whose products I have now reviewed on several occasions, usually to great rapture and applause (mine, concerning the quality of the product in question, as opposed to reader’s, concerning the quality of my reviewing) :laughing:

Pasted below are the IEM details from authorised dealer MusicTeck’s website:


This link also has photos and explanations of the tech that features in these IEMs.
The Fusang retails at USD $4’588. A bit of background might be helpful here, for those who are relatively new to this IEM. So, earlier this year, UM released the latest (and probably greatest) edition of their flagship IEM, the Mason.

In this case, it was called the ‘Mason Fabled Sound’ (or ‘Mason FS’ for short). It retailed at an eye-watering (and indeed Traiili-competing) $6k.
Nevertheless, it attracted quite a few buyers, along with glowing reviews.

A bit further down the road, UM released a cosmetically altered version, the Mason Fusang (generally just referred to as the ‘Fusang’). This featured more conventional resin-based shells (as opposed to the rare Cholla wood bodies of the Mason FS), and where the Mason FS featured the more expensive Attila cable from PW Audio, the Fusang features the less expensive (but still fairly premium) ‘Purple Charm’ cable, which is another PW Audio produced cable.
This offered essentially the same sound quality as the Mason FS (it’s been quoted as being maybe 5% different from the Mason FS) at a reduced price.

Personally, I actually prefer the shell design and cable appearance from the Fusang, so I for one was delighted to read about this new model!
So, going forwards from here, when I refer to the Fusang, pretty much all of those comments should apply equally to the Mason FS.

Now, UM – outside of its venerable world-class all-BA offerings – have been busy shaking up the IEM world with their hybrid (quad-brid!) models, particularly through the introduction of the use of Bone Conduction Driver (BCD) technology. Furthermore, they have been continuing R&D on their BCD design, first with the original MEST, then with the MEST Mk II, and now with the Mason Fusang (and Mason FS of course too).

The BCD featured in this IEM represents the pinnacle of that evolutionary process thus far, featuring a BCD that covers the entire frequency spectrum of the IEM, along with a redesigned housing for the driver that further contributes to its performance and character.

Indeed, one of the comments from UM regarding the Fusang was that they felt they’d pretty much reached as close to perfection as they were going to get with regards to tuning an all-BA flagship IEM (after several iterations); the introduction of the BCD was their way of seeing how they could evolve that sound even further, whilst still staying true to the BA-based signature build.

Disclaimer: I was provided with the Fusang free of charge, in exchange for my honest opinion, which is indeed what I shall be providing! My thanks to UM and MusicTeck for making this happen.

So, with all this introductory preamble aside, I suppose you’ll want to see how these things actually look in real life? Alright, go on then..
Photos coming up. In, perhaps unsurprisingly, the following section titled ‘Photos’


Build Quality and accessories:

The Fusang are solidly built with no visible blemishes or flaws of any kind.
The only small criticism I could level at them (same as with MEST Mk II) is that if they were going to go with the conventional 2-pin design, then I would have preferred the sockets to be recessed within the body of the IEMs, so that they don’t have the less attractive part of the connectors sticking out (or used a different 2-pin plug on their cable), or that – if there wasn’t enough room available inside the IEM body to do that – then they’d gone again with the same design used on the original MEST.

This small caveat aside, the Fusang comes in what I personally consider to be an improved design aesthetic, with a black carbon fibre appearance with thin purple lines appearing to be etched into the surface; a detail which is further complemented by the somewhat unusual choice of a tasteful purple cable. Anyone with goth leanings will doubtless find this black and purple combo to be a source of great joy and Cthulu-esque profundity, but I’d say it has a universal appeal too. They’re one of the most attractively designed IEMs I’ve seen, with classy logos (the artistic-looking Fusang tree on one earphone and the UM logo on another) and a visually coherent colour scheme.

They come with a 0.78mm 2-pin OCC copper Litz 8-wire cable, which can be terminated with your choice of plugs.
After a period where – due to issues with a supplier – UM were only able to offer 3.5mm or 2.5mm options (albeit with a free adaptor included), it’s really great to see the 4.4mm option back on offer, and this was indeed the one I chose.

Again, I just want to praise UM for continuing to offer a choice of cables; I’ve seen far too many TOTL level IEMs being released with just a 3.5mm or 2.5mm cable, and no options. Choice is king! Let the consumer choose the one that fits their needs!
(Layman1 climbs back down from his soapbox)

The cable here is 8-wire, which I was happy to see personally. It is, I must advise you, rather heavy and not the most flexible of designs. However, I have no trouble using it on a daily basis and haven’t had any issues with microphonics or fatigue. And plus, all that weight is offset by the sheer gorgeousness of the thing :D

The Fusang comes with a good range of accessories.
As can be seen in the photos, in addition to the various things included previously such as premium Comply ear tips, and an artisan Dignis leather case, the Fusang comes bundled with 3 various-sized pairs of Sedna Xelastec ear tips, which would normally set you back $30 or so by themselves, not to mention a completely upgraded cable offering (which I just mentioned).

I think the only criticism I could level at the Fusang in terms of accessories is that they’d already raised the standard so high with their MEST releases (which were sub $1500 releases). As such, for an IEM costing 3 times as much (4 times for the Mason FS!), it’s perhaps a bit of an anticlimax to have a set of packaging and accessories that are virtually identical to a much lower-priced model. An almost identical leather case, albeit with a slightly different design (I actually preferred the design of the case bundled with the MEST models personally) and same box and packaging. I think for a flagship release – especially ones at such lofty price points, perhaps UM could raise the bar a bit.

Having said that, it’s still a good range of accessories (particularly the ear tip selection), it’s just that they’ve kind of spoiled us for choice with previous releases already!


Regarding my gear and music for testing, I have a few tracks which I’ve only found available on MP3; the rest are FLAC or WAV in 16/44 or 24/192, with a few DSD56 tracks sneaking their way in too.
For the purposes of this review, the sources I chiefly used were the Sony WM1Z (using MrWalkman’s ‘Midnight Plus’ free custom firmware), iBasso DX220MAX and iBasso DX300 (with AMP12).

The Fusang has been an interesting experience for me. By way of a bit of background regarding my own preferences, my tastes have evolved over the years I’ve spent in this delightful (albeit wallet-busting) hobby. I started out (pre-audiophile days) desiring the earphone with the most bass (X-Bass anyone?!). As I got deeper into the audiophile rabbit-hole, I became enamoured of the neutral-reference sound signature. I think this was due to being entranced by the levels of detail retrieval, along with clarity and size of soundstage and separation. Then I began to appreciate and embrace the qualities that more a more warm and organic sound signature had to offer. I think since the overall quality and range of choice of IEMs has skyrocketed in the last 5+ years, it’s now eminently possible to enjoy stellar levels of technical performance outside of the neutral-reference tuning, which has allowed me to appreciate those benefits in conjunction with more musical sound signatures.

Things like note weight, note thickness, warmth, richness, impact, slam and rumble have all become qualities I’ve found quite addictive in various IEMs. Not to mention the appeal of the hybrid designs, with all the sound qualities the various drivers have to offer.

I first reviewed the Mason V3 a few years back, whilst I was still (I think) mainly favouring the neutral-reference tuning. I found that to be a remarkable IEM that would still give most within its genre a run for their money to this day. So now, I have come full circle, via heavily-coloured (sonically speaking) IEMs such as my beloved Stealth Sonics U4 and EE Phantom, via audiophile bass cannons such as the Legend X and Nemesis, via vivid, hard hitting technical paragons such as the MEST models, all the way back today to the latest UM flagship in their traditionally all-BA neutral reference model.

I have to admit, I was a bit apprehensive how I’d feel, coming back to this kind of sound signature after all the gear I’d come to love in the intervening years between now and when I reviewed the Mason v3 some years ago. Would I find it anaemic or unsatisfying?

Could I, as a reviewer, set aside my bass-head predilections and review this IEM objectively, when I might be constantly feeling disappointed by the lack of low-end power?
Read on, intrepid adventurer, to find the answer to this question, and indeed many more!


So, let’s get this out of the way, first up; the Fusang is NOT a bass-cannon. Obviously, it was never designed to be, and that’s ‘OK’. The good news is, it’s far better than I was expecting.

I find it to have a fairly linear tuning in the low end (and indeed overall); there’s perhaps a slight lift in the mid-bass, but I do like that the sub-bass extends deep.

The bass is – as one would expect from a BA-based implementation, fast, accurate and tight.

However, this is where those bone conduction drivers start to work their magic; there is a presence, power and precision here that astonished me.

By way of an analogy, in sports and martial arts, there’s power that can come from size and muscles, but also power that can come from perfect technique and precision (Roger Federer in tennis and Judd Trump in snooker spring to mind immediately; I’m sure there’s many other examples!). This is the kind of power that I feel the Fusang brings.

It’s always controlled, focused and harnessed; never muddy or loose or flabby.

The Fusang surprised me with the amount of impact and slam it was able to reproduce.

Would I like MOAR bass? Of course, I’m Layman1 :D

I funk, therefore I am.

But can I love the Fusang despite it not being a bass-cannon? Absolutely.

I keep coming back to it because it has enough to satisfy, and it just does it so ridiculously well, with remarkable tactility and texture as well.


This is the aspect of the Fusang which has probably gained the most praise, and rightly so.
Despite the relatively neutral-reference signature, there’s still a small tinge of warmth and musicality here, but what really stands out for me again is the note weight. The notes aren’t especially thick, but they are weighty, with a real presence. This does wonders for acoustic instruments and both male and female vocals, but also extends to electric guitars and indeed most things I fed into it. As with the lows, there’s a gorgeous texture and tactility that I usually find in dynamic driver-based IEMs.

Finally, there’s also a pretty unique quality that seems to come from the BCD’s; there’s a subtle kind of reverb effect on some vocals and instruments. It doesn’t sound artificial to me in any way; indeed, it actually enhances the realism greatly and makes me feel like I’m there in the room with the artist(s). It’s as if I’ve gotten used to how regular IEMs present vocals and instruments, and when listening to the Fusang, I’m reminded about what they sound like in real life. It’s also a physical feeling, as much as a musical one.

I listened to two tracks by The Stranglers, from their ‘About Time’ album, where the main singer had been replaced by someone who sounds a bit like a lounge singer but which I actually really like. ‘Golden Boy’ and ‘Sinister’, two outstanding tracks from the album.

Golden Boy opens with a kind of humming, thrumming sound, and I noticed, from around 11s to 15s into the song, the Fusang delivers a level of physical power to this bit that I’ve never heard before. This is followed almost immediately by some percussion (drum rim taps I think?) and again, there’s a remarkable level of tactility and realism here.

The track ‘Sinister’ opens with a mixture of kick drum and snare and a cello comes in shortly after. That cello sounds remarkably good; there’s a real grain and texture to it with the Fusang, as well as a delightful depth and weight to it.

Moving on to something completely different, it’s my favourite classical opera review test track, Handel’s Lascia la spina, sung beautifully by Hong Kong based soprano Alison Lau.

What I always look out for here is a point from 14s to 16s, where the strings all descend into lower notes. I love it when an IEM renders this part with real body, richness and weight, and the Fusang does not disappoint in this regard. Even more so, considering the other IEMs which I typically love in terms of how they handle this section of the song are usually ones that are rather (or exceptionally) warm IEMs, such as the EE Phantom and Stealth Sonics U4.

So for a relatively neutral IEM like the Fusang to still deliver the goods here is high praise indeed.

One more here; R.E.M. ‘Nightswimming’ (24-192 HDTracks). The piano on this is just jaw-droppingly good with the Fusang. SO much sustain, note weight, and a stunning resonance that seems unique to the Fusang, likely a product of the bone conduction drivers.


To continue with The Strangler’s ‘Sinister’ song notes, furthermore, some of those IEMs that excel with the strings as they swoop low, do comparatively less well with the sparkly harpsichord in the background; sometimes that sparkle is a bit muted or dull, but here is has a lovely soft sparkle.

Generally, I can commend the Fusang for those who might have a sensitivity to treble (such as myself) or upper-mids for that matter. Even with tracks such as the aforementioned Alison Lau opera song, where she hits some piercing highs which can trigger my sensitivities with other IEMs, the Fusang remains marvellously smooth, yet never dull or rolled-off.

I feel the Fusang highs are carefully balanced with the lows and mids. They suffuse air and separation throughout the whole sound signature, without any shrillness or harshness. There’s enough brightness and sparkle to keep things feeling alive and captivating, but this is not an excessively ‘trebly’ IEM.

And as if on cue…

Technical Performance:

Yeah. It’s really good. Haha.
As I’ve mentioned, in addition to the expertly implemented BA drivers, those Bone Conduction drivers have worked some flat-out magic here with this IEM. It presents details in a way I’ve come to appreciate with other IEMs; naturally and organically, not in terms of tonality but in the way I just naturally notice details as an holistic part of just enjoying the music. It’s not an ‘in your face’ kind of presentation of detail, or one which is constantly drawing one’s attention away from the appreciation of the song as a whole.

Nevertheless, I found myself consistently hearing things I’d never noticed before (which, given the amount of quality gear I’ve been privileged enough to hear over the years, is a noteworthy observation). Imaging and layering are simply superb and the degree of separation is excellent too. Each component of a song (instrument, vocal) is easily picked out and can be focused on at will. Soundstage is an interesting one.. I think it extends quite far and is holographic for sure, but I only noticed the extent of this extension on certain tracks (‘Love Dies’ by Club 8 for example); most of the time, the staging of the Fusang seems to be smaller, with more of an ‘intimate venue’ type of feel; spacious, but you’re close to the action, not 50 meters away up in the high stands.


Well, I know that here people would normally expect to see comparisons.
I decided to omit them, simply because I'd be comparing apples and oranges.
I don't as yet simultaneously own any other IEMs worth $2k+, and of those $1k - $2k IEMs I do own, they are so very different in sound signature that I can't really see much basis for comparison. Add to that the frankly unique qualities of the Fusang and I hope you'll appreciate why I decided to simply let the Fusang speak for itself here. As it were. :)

Sources and synergies:

I have predominantly used the Sony WM1Z in this review, as I found it’s smoothness and musicality lent itself rather well to the extensive listening sessions this kind of review inevitably entails.

With the DX220MAX, I found the Fusang to sound more crisp and slightly less smooth, more open and airy, and with a small increase in note weight. More neutral in signature, but still very musical. Details seemed to pop out more noticeably vs the WM1Z. Low end slightly more impactful. A really nice shimmer.
With the WM1Z, I found the sound to be more warm, organic, full-bodied, smooth and musical.
It has great timbre and is effortlessly engaging.

I found the DX300 (with AMP12) to fit sonically somewhere in between the WM1Z and DX220MAX; it has the lovely shimmer of the DX220MAX, and detail retrieval is almost on a par with that DAP too. It seems to have more richness and power than the WM1Z, but bears some similarities to the WM1Z with a fairly warm and organic signature. Soundstage is on a par with the WM1Z, and there’s not quite that huge sense of air and space that I get with the DX220MAX.

So, as I remarked in a previous review, if you were reading my notes on the DX220MAX and WM1Z synergy and thinking “Gosh, Layman1, if only there were a DAP that could combine some of the great qualities from each of those two!” then today’s your lucky day :D

Overall, I felt the DX220MAX had the best synergy as it pretty much doubles down on everything that I love about the Fusang; astonishing note weight and presence, fairly neutral-reference tuning but with a tonne of musicality, superb detail retrieval. It expands out the soundstage and separation of the Fusang, bringing a significant increase in air and spaciousness, but still with no loss in richness and impact.

The only negative (and the reason I still often reach for the WM1Z, is that it’s such a pinpoint, vivid and detailed presentation, that I sometimes find myself getting a little fatigued with long sessions. However, I have sensitivities to various sounds/frequencies, so this may not be an issue for most.

The WM1Z on the other hand, is effortlessly smooth with an organic musicality that I can just get lost in for hours. So, the choice is yours :)

Bonus cable roll (!!):

Eletech Plato X Socrates 8-wire (limited edition):

It’s a testament to the quality of the stock cable that the changes I hear are not that pronounced at all. With other IEMs and their stock cables (EE Nemesis and Phantom for example), I heard a significant (positive) difference with the Eletech cable.

With the Fusang, I hear a small increase in clarity, shimmer, impact, soundstage and separation when using the Eletech cable.

I feel the stock cable has a bit more smoothness and musicality though, so it’s probably going to come down to personal preference.


Well, the Fusang has pretty much blown my mind. It really is that good.

It does things I’ve never heard other IEMs do (courtesy of a stellar bone conduction driver implementation). It manages to take the neutral-reference template, stay quite faithful to that, whilst injecting a musicality, weightiness and presence that has to be experienced to be believed. Technical excellence combined with pure soul.

Even for an unabashed basshead like myself, I’ve felt nothing to be lacking here.
I’ve thrown every genre I can think of at it and loved what I’ve heard.

I cannot really comment on whether it merits a $4k+ price tag, since such matters are personal and relative. What I can say is that if you are willing and able to part with such a sum, then I’d highly recommend giving this IEM some serious consideration.
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Nice review, totally out of my budget, but I would love to hear it, maybe at the next Canjam...


Headphoneus Supremus
From a bass head to a bone head
Pros: stellar vocals, instruments
speaker like physicality
extracts a new dimension from recordings
Cons: soundstage is small, hinders complex passages
doesn't work for synthetic music well
not versatile across multiple genres
Disclaimer: Fusang and Fabled Sound Special Edition are similar iems. They both use the same driver topology. Fabled Sound differs by included a premium cable (Attila) and a limited edition luxurious shell design. I suspect this review can be applied to Fusang, however I have not auditioned the Fusang so I will leave such a comparison to others.

“Every once in a while, a revolutionary product comes along that changes everything” - Steve Jobs

Music. That’s why we’re all here. This universal language that transcends limitations of spoken word. A language that can tell stories of pain or triumph, a drama from a different era. A tool to help us relax at the end of a stressful day or give us that extra push when needed. I have eternal thanks for the artists who can hone their craft of being able to stimulate just the right part of the brain at the right moment to evoke an emotional reaction. Whether we traverse the path of nostalgia or trying something new, these sonic visions are those that can be remembered for many years after.

Before and Now

A key contribution to this journey of musical enlightenment is of course, the gear. At times I do feel somewhat guilty, I can become too focused on the gear and not on the music. In an effort to get closer to the artist, one can engage in the gear chase or ‘upgrade-itis’. This is the endless search for the right gear and yet…still wanting a little more if possible. Many of us remember purchasing a gear, declaring it to be ‘end game’ on the forums, then only to upgrade it soon after. For some, it’s that touch of extra sub bass that’s needed for the visceral feel, for others more treble extension and wider soundstage for the desired sound.
For the past several years, the summit tier level of iems have yet to realize a breakthrough comparable to the explosion of developments in the low to mid tier of iems. Even accounting for the infamous Oriolus Traillii, with a nearly perfect record on Headfi, nearly all the iems on the market are currently using well known technologies (BA’s, EST’s, DD’s and in some cases planars).


These conventional drivers in iems, ranging from Blessing 2 Dusk to Oriolus Traillii, operate on the same principle however. Regardless of the driver technology the manufacturer uses, they all push air into the ear drum. This is known as Air Conduction (AC). While a Legend X can sound quite different from an Anole VX, one can somewhat appreciate the differences in sound signature in a written assessment. When perusing an iem review, many of us can quickly understand terms such as ‘DD slam’ or ‘BA bass’ without even auditioning the featured iem in question.
However a review of Mason FS will not be afforded the advantages of iems that have come before it. The Bone Conduction (BC) driver and how Unique Melody gave it the prominent role it plays in the Mason FS/Fusang requires one to demo it to understand. I will attempt to describe the magic behind the combination of BC and AC driver implementation, but I can’t stress enough how this iem (Mason FS and Fusang) requires an audition.


*credit Unique Melody

Mason FS employs a dual sided Bone Conduction driver (500Hz-20kHz) along with their 12 BA array. Bone conduction is a driver technology which is famously used by Unique Melody in their IEMs such as MEST. Simply put, bone conduction works by piezoelectric ceramics which bend metal vibration pieces. These metal pieces generate a vibration which travels through the IEM shell, your ear and to the temporal bone. The design intent of employing the BC driver is to add weight and density to music which conventional air conduction technologies are unable to replicate.

BC driver aside, the Mason FS employs 12 custom designed large sized BA’s arranged in a 4 Bass, 4 Mids, 2 Mid Treble and 2 Treble configuration. In conjunction with the BC driver, this system is controlled by a 5-way crossover.

Special Edition

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In the box, Fabled Sound includes a cable specially tuned for Mason FS, the Attila. Attila is a collaboration with PW Audio and is an upgraded version of the 1960s 4 wire. I purchase cables based mostly based on aesthetics and ergonomics. My ears are not gifted enough to hear the differences in cables unfortunately. What I will say is Attila is a much-improved version of 1960s 4 wire and many Mason FS owners love Attila. However, those looking for minimal microphonics may want to look at TPU cables such as Eletech’s Iliad or Aeneid. Disclaimer, I am picky with microphonics and am switching out Attila with an Eletech Aeneid cable. Most of my testing with Mason FS has been with Attila, to best capture Unique Melody’s design intent.


I am lucky enough to straddle the headphone world, iem world and speaker world. I’m sure most of us can agree that speakers offer the very best audio experience possible. On the other hand, this requires space and money. Those with the funds for speakers may not have the space, and others may have the space but lack the required funds. One can stretch a dollar more in the iem world than the headphone world. This can also hold true for the headphone world when compared to the speaker world. The cost no object headphone system, Sennheiser Orpheus HE1 costs a mere 59k USD, while a cost no object speaker system can exceed 1 million dollars (not including room costs).

Nevertheless, speakers have this physical quality that no gear in the headfi world can replicate, regardless of price. It’s that feeling of a sound wave traveling through your entire body and allowing you to feel the music as if you were there. I played piano for nearly 10 years and have a good understanding of how a note should feel physically. Not just as a listener, but as a player. As much as headphones and iems try, they have not been able to overcome this challenge of physicality. This physical connection to music is perhaps why, up until this point, I’ve seen myself as a basshead (in the iem/headphone sphere), or at least someone who places a premium on bass presentation. When using iems and headphones, I am keenly aware the music is emanating from two points on my head (or in my ears). This goes for even summit level gear such as Oriolus Traillii and Hifiman Susvara.

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Last year, I embarked on a home project to install a speaker system. Thankfully this project has been completed after several covid related logistic delays. However, my speaker journey led me to a discovery in how I enjoy iems/headphones vs speakers. With iems/headphones, I tend to prefer equipment that has a stronger bass presence but with speakers it seems I prefer reference leaning tunings. Perhaps this shift in personal preferences can be attributed to how elevated bass in iems/headphones may serve as a compromise to make up for the lack of physicality speakers can provide. The way a soundwave travels through the floor on a full range speaker and then propagates throughout your body contributes to the ultimate form of audio reproduction.

Feeling the Vibrations

Mason FS Showcase Music:
  • Fall on Me by Andrea Bocelli
  • Paganini 24 Caprices: Sueye Park
  • We Are One by Yao Si Ting
  • Sonorite by Tatsuro Yamashita Sonorite, Track 4 (忘れないで)
  • Sugar by System of a Down
  • Mozart Piano Concertos by Murray Perahia
  • Essential Yo-Yo Ma by Yo-Yo Ma
The Mason FS has altered my listening patterns. Previously, I would reserve acoustic instruments and vocals with my full range speakers, as this this is what they were designed for. Mason FS allows me to take my speakers with me, wherever I go.

Mason FS brings life to instruments (plucked strings, electric guitar, wind instruments, piano etc) and vocals. The sensation of a vocalist’s voice vibration travelling into my jaw approaches the authority speakers can deliver. This is likely due to the magic of the Unique Melody’s Bone Conduction driver implementation. Such a rendition is more intimate and speaker-like than anything else I’ve heard in the headfi realm. Listening to an orchestra, I feel sweetness of the strings and the meaty cello as if I am in the venue. FS communicates the texture of violin I’ve only felt when I briefly played one. This is beyond just bass, this is physicality. And this physicality is traveling through your ears and seemingly into your jaw.

This incredible presentation doesn’t just extend to classical music. The same holds true for rock, such as one of my favorite rock test tracks, Sugar by System of a Down (time code 0:20-0:30). Feeling the texture of the guitar in between Serj’s raw rendition reminded me seeing them live those many years ago.

Air Conduction drivers seem to be at a disadvantage in comparison. With other equipment, such as Oriolus Traillii or Hifiman Susvara, I felt that I was having the absolute best experience listening to a recording. The Mason FS combines the strengths of iems and physicality of speakers to create something unique and in its own category.

Mason FS allows you to feel the music as if you were playing the instrument or sitting inside the vocalist’s throat. This is unlike anything before it.

The Fabled Sound

Mason FS is tuned to be natural and reference oriented. Brief note on the tuning UM chose. This is neutral, but pleasant. Almost sweet sounding and very natural. The Mason FS will take after which ever source you pair with it. As I prefer slightly warmer house sound, I paired with the Shanling M8, and Shanling is one of my favorite house sounds. This gives Mason FS a neutral with a tilt towards warm. Other reviews have note Mason FS is neutral warm from the start, but I’m waiting for my N6ii to come back from repair to confirm this.


credit: pixabay images

Regarding soundstage, this iem is has a spherical intimate staging. Think of a small jazz club venue vs a large opera house. This iem shines with solo performers that one would typically see perform in such smaller venues.

This tuning is a love letter to musicians. I am keen to see a classical musician or guitarist review this set. For those looking for a fun/engaging iem, this is not the one for you. Perhaps Unique Melody could create a Mentor FS to address this? :wink:

The bass presentation is well defined and accurate just as you expect from a BA. It’s not bloated, but firm and well balanced. The mid bass is slightly elevated, but perhaps this is the M8 influencing the presentation. This is not a lean bass presentation, however. For the longest time, I’ve owned single DD iems as BA bass didn’t provide me the authority that was needed. Not to worry with Mason FS. If the song requires a firm bass note, the Mason FS delivers with absolute authority. In this regard, Mason FS bass reminds of Wilson Audio bass presentation. The bass is reserved but when needed it will punch with absolute authority and is clean. The BC is taking a backseat here and is reserving itself for the mids.

This is where I find Mason FS beats out iems and headphones. This is where your money is going. The BC vibration creates this extra dimension with vocals, this ‘air’ that many folks are describing. The Mason FS gives vocalists their own dimension, their own room to perform. The echo I hear with Tatsuro Yamashita’s album Sonorite, Track 4 (忘れないで) gives atmosphere that I’ve only ever heard with speakers. The reverb in the track is lifelike, Yamashita’s voice is vibrating through your ears, the guitar feels like you’re strumming the strings, it’s unbelievable.
Paganini 24 Caprices by Sueye Park will bring any violinist to life. Hearing the vibrations is one thing, feeling them interact with the air is another.

I’m trying to be objective here, but this presentation so unique and a step above than everything else I’ve heard it caused a major reassessment in my headfi career. This isn’t a curveball UM has thrown, it’s a whole new ball game.

Restrained, in a good way. I feel UM has tuned the treble around the mids and pulled away unpleasant harshness one may find in a IER Z1R so the listener can enjoy the mids more. Given the BC is a full range, I think the BC assisting in the treble more so than in the bass section. Perhaps this is contributing to Mason FS’ nonaggressive treble presentation. I can see some calling the treble a weaker aspect of this set, but in the context of the mids and bass, the tuning is thoughtfully well done. For cymbals, xylophone and the triangle the BA’s and BC work to present an accurate rendition of the sparkle we expect from these instruments. For genres like EDM, this treble presentation doesn’t seem to work.

However, there are caveats to Mason FS.

First, you need the right music. EDM or synthetic music will not sound right with these. If we distill what Mason FS’ strengths are, we can anticipate its weaknesses. Mason FS needs music which generates vibration from an organic source. For a vocalist or an instrument, we can listen to the first rendition without any additional processing straight from the instrument. Synthetic music however requires processing through console and to a transducer, through which it is heard. It is an artificial recording in a sense. In this way, synthetic music like EDM is composed for air conduction drivers from day 1, whereas classical music recordings are attempting to capture the natural sound straight from the instrument. I love my EDM, and Mason FS just doesn’t work with this genre. To give you an idea, I prefer Blessing 2 Dusk for EDM. It will be interesting to see how Unique Melody approaches this challenge for the ‘wilder’ counterpart to Mason FS, the Mentor FS.

Next caveat, the staging is intimate. I’m not sure whether this is an intentional choice by Unique Melody or a limitation of the Bone Conduction driver, however at this level of iem I expect the gear to grow with the music. While orchestra does sound excellent on this set, it fails to replicate the venue to the degree my other reference gear can. When a recording starts adding multiple voices, multiple instruments, the Mason FS can’t seem to scale with the music.

The third caveat is Mason FS is a little picky with source gear. Mason FS does not require very expensive gear, but it does require the right gear. Perhaps a quirk of Mason FS leaning into the Bone Conduction for sound presentation. The DAP you pair Mason FS/Fusang with needs to exercise plenty of control to achieve the right dynamics. A popular choice with Mason FS is Shanling M8, I have been using this combination for most of the time I spent with Mason FS. On the flip side, Mason FS scales immensely with the gear you pair it with. Again, I suspect this is BC driver scaling. When I paired the Cayin C9 headphone amplifier with Shanling M8, the result was so good I ended up listening until the M8 ran out of battery.


After experiencing the marriage of BC and AC on Mason FS, I’m reassessing how to perceive value and sound in the headfi realm. We’ve witnessed pricing in this hobby shoot higher and higher with mostly incremental improvements on conventional technologies. Unique Melody however, offers a new approach in their high end offering and extracts a new dimension out of recordings. Mason FS and Fusang, are gear which showcase leaps forward in acoustic reproduction, technological innovation and almost live up to expectations the price tag set. At this level, I expect excellence in every genre at the very least. The fact I need to look to Mentor FS as a potential solution to Mason’s shortcomings in certain genres is a prominent negative. However, after using Mason FS, everything else just sounds off, empty and hollow. Factor in that you can get Fusang at $4580 (Musicteck will give you a better price if you ask) softens the blow somewhat.

One may do a double take at manufactures who charge similar prices for air conduction sets. Headphones, once touted as the superior alternative to iems, now stands challenged by bone conduction as well. Even the best gear like Susvara and Traillii are constrained by the fundamentals of Air Conduction, unable to deliver the extra dimensionality Fusang and Mason FS can deliver.

We are at the first inning with BC implementation in high end hifi gear. The key challenge UM needs to deliver is, can Mentor FS address the shortcomings with Mason FS and complement it? Can it provide the larger soundstage and work with synthetic music like EDM?

Closing one chapter, starting a new one
The question you need to ask, do you listen to the right music? Are you interested in a novel experience that may alter your perception of other gear? If so, get your packing tape ready, you may go down my path and sell everything. Unique Melody is offering, what I believe, the next chapter for iems and possibly the future of audio. I’m not sure where the journey will take me next, but I do know one thing. I am a bone head :wink:


Testing Equipment:
Sony DMPZ1, Shanling M8, Cayin C9, ifi ZEN DAC Signature
Eartune Fidelity U Tips (strong recc), Eletech Aeneid, Unique Melody Attila.
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Fantastic review, well written, and the examples you used were excellent. It's also refreshing how honest you were about the Mason's shortcomings, and described specifically what sort of music it's best suited for. Too many reviews praise or critique the gear without specifying music choice, which doesn't make sense considering that's utlimately what it's used for. Well done, look forward to future reviews.


Headphoneus Supremus
The new reference for reference
Pros: Technical ability
Extremely linear FR
Coherent, engaging
On the colder side
Excellent build quality/design
Cons: On the colder side
Average staging width
Average accessories/stock cable
Disclaimer: I purchased the Mason FuSang at a discount in exchange for my honest impressions. Unique Melody were also very kind to send me their Attila for the purposes of this review - While the FuSang as a whole was nowhere near a free sample, I'd personally consider these significant "incentives" on the part of MusicTeck and Unique Melody, so to correct for that bias I have done my best to outline everything I feel like would be a more negative aspect of the FuSang in order to remain objective and overcome any involuntary biases my interaction with them may have created.

When the Mason Fabled Sound first got announced I almost purchased it several times. It went in and out of my MusicTeck cart time and time again, but I managed to resist for long until the version for mere mortals got released at 1400$ less - the FuSang. I was actually extremely pleased, because I love the design (I'd say more so than the Fabled Sound even), and being the cable-rolling fanatic that I am, it was a no-brainer. 3 days later (thank you DHL I love you), the FuSang was delivered, and a few owners actually warned me of a certain "slow love" relationship they had with the Mason, where at first they weren't as impressed but slowly it grew on them.

That was all quite foreign to me, because the FuSang was one of those proper love on first sight (or listen) experiences for me, quite reminiscent of the Thummim and the Elysium before that.


1. Packaging, accessories and everything else that makes it into the drawer

The FuSang comes in a pretty decent, but basic box - basically the same as the MEST 2, with a very nice carry case (I actually use it all the time because I can shove any cable I want in there, a second cable if I am going to be rolling on that day, and the PAW S1. With the release of Apple Lossless, the little S1 has actually been seeing a lot of use but more on that later.

The eartips selection is lovely - UM silicone tips, Comply foam and Xelastecs (them sticky tips that end up sucking out every ounce of earwax). Oddly enough pretty much none of them worked for me and the Mason, and I ended up settling with the AET08 (medium) from Acoustune. I personally haven't found that the eartips make any massive difference when it comes to the FuSang's sound as long as you can shove it decently deep in your ears. Once the earpieces touch somewhere in the middle of your brain you know you've achieved a good fit - whatever gets you there

2. Build quality and cable

The FuSang has a very nice shell - I'm not a huge fan of acrylic as I've mentioned a lot of times, but UM have made up for that in the build quality, an original-enough design and their carbon fiber magic that's quite unmistakable. I like that at no point does the FuSang look generic, and is quite easily identifiable as UM-built IEM.

The stock cable... eeeeeeeeek. Very stiff, very uncomfortable. 8 wires tend to be a little softer in my experience but that really is not the case here. Maybe it becomes a little smoother with frequent usage, but I replaced it pretty much immediately.

3. Sound

Let's gooooo! This is the best part of pretty much every review - if I took the time to type up a full, complete review of an IEM it generally means I've really clicked with it, and the FuSang is no exception to that rule. I'd go as far as saying it is one of the heaviest honeymoons I've had ever, right up there with the Thummim and Elysium. I purchase and receive a ton of IEMs pretty much monthly, and all that money blown and lost is 100% worth it for those few IEMs I really, really enjoy. It had been a while since I've been obsessed with anything, great times <3

The Mason FuSang is to my ears, an interpretation of reference above all. It is a very neutral, very clean and linear IEM. There is no emphasis just about anywhere along the FR, with a certain "effortless" sensation. The midrange is where the FuSang shines, displaying an airiness that I have no seen performed by just about any IEM, at any price point, ever. I wouldn't put it down as a mid-centric IEM, but it is the part of the FR that demands the most attention.

As to how musical it is... I'd personally put it towards the colder end of the spectrum. It is absolutely not a thin-sounding IEM - quite the contrary, there's 0 lower midrange suck-out, but the overall sensation it gives me is towards an IEM that stays faithful to the voice of the performer as opposed to infusing it with a sense of "romance."

Lastly, as a general sentiment for the tuning intention of the Mason, I’d say it is an IEM that relies on technical ability above all for resolution – there are none of the typical upper midrange/lower treble boosts to give you a sense of an ultra-resolving monitor. It’s pure speed and dynamics IMHO.

The bass of the FuSang is very well balanced, with what I'd consider to be a very slight mid-bass emphasis. I really, really enjoy that, and after spending a bunch of time with the A18S, it's something that I've come to almost demand - while it takes away from some of the clarity, it gives you such good imaging in bass-heavy tracks - I am able to hear exactly where and when each punch happens, it completely dodges that "diffused" sound. Qualitatively, the bass is an unmistakable BA, that aims to sound like a great BA. Great speed and control with okay texture. It matches my preferences very well, but I personally wouldn't recommend it if you're after an especially organic, layered and textured bass response such as the one you'd get from dynamic drivers.

I always felt like both types of bass had their place, and the FuSang is no exception to that rule - the bass fits in perfectly with the rest of the FR both qualitatively and quantitatively. As I mentioned earlier, the FuSang is a reference, somewhat colder monitor, so a warm and "wet" bass just doesn't feel like it belongs. That was one of my main issues with the EE Odin, since I felt like there was a certain mismatch between the midrange/treble presentation and that of the bass

The midrange of the Mason is what IMHO helps it move from "high tier" into "hardcore TOTL." I already mentioned this is in my initial impressions of the Mason, but it manages to infuse vocals with an airiness and “dispersion” that I haven’t experienced in any IEM or headphone I’ve heard before. I’d attribute that effect to the bone conduction driver, since it is especially atypical for BAs – I can feel it to some extent in instruments as well, but due to the colder, tighter nature of the sound it’s especially prevalent and noticeable in vocals.

In terms of frequency balance, it’s what I’d consider to be linear, but I’ve heard it described as “upper mid scooped.” The lower midrange is reasonably forward, which creates a really good sense of texture to my ears, giving instruments and male vocals a lot of weight and presence. As someone who listens to the likes of Yelawolf and Mick Jenkins a lot I really appreciate that – I can’t really deal with thin or shouty male vocals.

The upper midrange is what I’d personally consider as neutral/natural. 0 enhancement or forwardness of any kind. I always found forward upper mids to be a bit of an artificial boost which does more harm than good, so the FuSang earned big points in my book for avoiding it while still being able to deliver stupid amount of detail. That being said, listening to FKA Twigs’ thousand eyes I am still blown away by just how extended, full and euphonic her voice is, while being infused with that “airiness” I mentioned a few times. Pure bliss

The treble of the FuSang is in my experience especially responsive to cables – it’s relatively rare that I’ve seen any wire make such a difference to the highs, but it’s kinda all over the place in this case. With the Eletech Aeneid and Iliad I’d say the tilt is more towards the upper registers, while the Attila shifts the peak lower down and results in a hint of a roll-off.

Other than that, it is a relatively linear treble presentation, with no harsh peaks or sibilance. I wouldn’t personally call it especially sparkly – it focuses more on raw speed, keeping up with especially busy tracks and performances. It is somewhat reminiscent of the A12t treble, with some more presence since the FuSang is a noticeably brighter monitor.

On technical ability, the FuSang impressed me heavily, but not in the way I expected it to. Dynamics are its strongest suit I’d say (once again reminding me of the A12t), paired with especially good instrumental separation resulting in incredible detail retrieval. I really liked the description “detail that you can hear when you pay attention” as opposed to “the monitor bringing your attention to the detail.” It is all there, it is just up to you to sort of pick it apart and listen for it. The A18S is the first IEM that I really noticed that in, and I absolutely loved it since it is the technical ability that is doing the heavy lifting in terms of detail instead of relying on upper mids and treble.

The staging on the FuSang is alright, but alright is the word here. Good depth, great height, mediocre width. I would personally enjoy a more stretched-out stage, but compared to how outstanding everything else is about it, this is a small complaint.


4. Pair-ups

I have a relatively limited number of sources I got the chance to try the FuSang with, so some of this will be done based on extrapolation. The sources I have at my disposal are the Lotoo PAW S1 (still best dongle from what I’ve heard), the PAW6000, and the McIntosh MHA150.

The Mason scales incredibly well, but to me it is not an IEM that “needs” a high-end source to sound great. The Thummim for example was not worth listening off the PAW S1, which created a certain level of inconvenience. I’ve spent countless days listening to it off the PAW S1 and my iPhone, and while the dynamics aren’t as outrageously good as they normally are, and some of that midrange “airiness” is lost, the majority of the magic is preserved.

The PAW6000 is what I’d consider to be “everything you really need” to hear the FuSang at its best. Excellent staging, no real loss in dynamics, great detail across the board and a mostly unaffected tonality except maybe a hint of added bass decay. I’d love to try it with an LPGT but I’m waiting for either a really good deal on that, or a new release from Lotoo. I’ve heard the FuSang sounds especially good off the Ti, but the price commitment on that is kinda eeeeeek .

The MHA150 takes the Mason to an outrageous level of performance, but honestly I’ve experienced the same with the Noir, the A18S and the Thummim as well. I’d say it’s more of a testament to the MHA150 and what it does to anything that’s plugged into it than it is to the IEM itself. Either way, the resulting sound is slightly brighter, slightly more forward and more revealing, but at all times preserves its smoothness and absence of all harshness. The staging expands a fair bit in all directions and detail becomes borderline overwhelming.

The Mason is especially responsive to cables in my experience, and I dare say it’s actually comparable to how much it reacts to sources.

I tried the Eletech Plato, the Eletech Iliad, the Aeneid and the UM/PW Attila with it. Of the four, I’d rank them as Aeneid > Iliad = Attila > Plato. The Aeneid just sounds outrageously good with the FuSang, almost like they were made for each other. A mostly unaffected frequency response save for a boost in the upper treble to give that sense of airiness to instruments as well, exceptional dynamics and detail as well as a small boost to the musicality, mostly as a result of the added GPS texture. Amazing pairing, and one that is pretty much on the FuSang 24/7


The Iliad and Attila are both cables I’d consider to be good “alternative” flavors, but ultimately both miss the mark for me in one way or another.

The Iliad adds too much decay to the bass, which in my head messes a little too much with the whole reference tonality and presentation of the FuSang. It pulls vocals a little further back, which I never really mind but it just doesn’t quite sound optimal either. The Iliad is a cable that I consider to be especially holographic, but lacking that width expansion of the Plato and the Aeneid, so in that respect it ends up being an overkill on the Mason too.

The Attila, as I mentioned in another post, is one of the most outrageously good pairings for the 64Audio A18S, but not as much the Mason. It adds a healthy boost to the subbass and lower treble, which once again throws off that neutral/natural balance of the Mason. It is quite a vivid sounding cable, so if you’re looking for an even blacker background and a more forward, engaging presentation it would be the best choice, but to me, the identity of the Mason is more laid-back. Dynamics are however off the charts on it.


The Plato is too flat for the Mason, shooting past reference and into “lackluster”

5. Conclusions

The FuSang is what I’d consider to be the lovechild of the Elysium and the A18S. I can feel the identity of both IEMs when listening to it, in many ways taking the best of both worlds. While the Elysium is too musical for my current preferences, and the A18S can push into that reference territory a little too much, the FuSang balances just between the two in the most optimal way I could think of.

An incredible IEM, with a big dose of that special sauce, making it one of the best (if not the best) sound I’ve heard from an IEM thus far.



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Totally agree on the Aeneid being made for the FuSang! They were a holy crap moment when I swapped from stock purple crud -> Iliad -> Aeneid. Ugh I wish this hobby weren’t so expensive …


Headphoneus Supremus
Mason Fabled Sound - Freakishly Special
Pros: Incredible vocal presentation
Lifelike, nuanced & textured sound
Realistic stage presence
Neutral tuning without ever sounding flat or dull
Cons: Very, very pricey
Larger shells may not fit all ears
About Me

A few brief words about the lunatic behind the keyboard for this review. I became an “audiophile” a few years ago and started climbing the ladder to insanity pretty quickly. I started with some decent IEMs, a few earbuds, dabbled in headphones and eventually ended up on track to own almost every single flagship ever released. I do not believe I am a “reviewer,” per se, but instead just love trying gear and then writing about it when something really strikes a chord with me. You’ll notice a lot of my reviews I have posted are pretty positive and if I’m being honest, I don’t bother writing reviews on a mediocre product. Maybe that’s a polarizing, or lazy view, but I buy all my own gear and am not constrained to write about something I don’t want to. Liberating, really. That said, I’m also not as good as the real reviewers, so this will probably be more about the feels and the enjoyment factor than a true technical analysis. But hey, I promise to do my best either way. I've had a long journey with Unique Melody IEMs, so on that note...
My Unique Melody Journey

While it may not be super important to bore you with the other Unique Melody IEMs I’ve had, I am amongst the few that have owned: Mason, Mason II, Mason V3, Mason V3+ and now Mason Fabled Sound. You could say I am a Mason fan and you would be right, and the Mason IEM holds a special place in my heart because my son’s name is Mason as well. Does that make me biased? Absolutely and I committed to owning every one of them (although this one tested my price tolerance, but more on that later), so I had to have the Mason Fabled Sound as soon as I saw it. The Mason line, to me, has always stood for natural, engaging sound that never had an over-the-top sound signature. It was always a mature, refined tuning – something that is underrated in today’s bombastic approaches to sound. The Mason line focuses on the music, the nuances, the emotions within, and the Fabled Sound is the best of them yet.

The Fit, Finish, Accessories and Extra Goodies


I promised myself I would try not to immediately go here, but I have to and cannot resist. I own two IEMs in this price segment and both of them sound wonderful, but one comes with an incredible set of accessories and one comes with a cardboard box that belongs in the recycle bin. Now, with that out of the way, you get some really cool and unique stuff with the Mason. First, the IEMs themselves, which are crafted carefully with a stabilized and resin shell that looks quite unique (in fact, no two look alike). The shells are a gorgeous translucent blue with segments of wood that really make the IEM look special. Physically, they are on the large side, but they’re quite comfortable to me and the medium-sized nozzle accepts pretty much any tips I would choose to use (Spiral Dot++ for the win for me). The wood itself is apparently harvested from a Cholla, which is a type of cactus, normally found in the Southwest part of the United States and Mexico. Unique Melody isn’t the first to make these stabilized wood shells (Noble. Makes some incredible Prestige designs as well), but they give you some goodies in the box that show their commitment to outside the box thinking. In fact, you get a piece of the stabilized wood and resin that your very own IEM was crafted out of, which is pretty cool.


Moving along to what else you get, well, let’s talk about the cable. It is made by PW Audio and is called the “Attila” cable. It reminds me of the 1960 cable from PW Audio, which is definitely not a bad thing. Handsome black sheathing, UM-branded (and lovely) hardware and fancy shielding that makes it sound like unicorns singing in the night. I like the trend of newer flagship IEMs coming with top of the line cables and this package takes it to the summit-fi level. For that reason, I didn’t bother with cable rolling (yet) and will update the review if I do. I’m normally overly loud about throwing all stock cables in the trash can, but not here – no way. For better or worse, UM has abandoned the 4-pin “Dual Tone” cable, which allowed you to change between different cable material configurations. For me, this was painful because I owned the $2,100 Effect Audio “Phanes” cable that was an 8-wire beauty that no longer works on the latest flagship, but I think the general audience will greatly appreciate that the UM flagships are now standard 2-pin. The sky is the limit for cable options, but it’s sort of a moot point if you plan to enjoy the high-quality stock cable. Only complaint here is that it’s a little stiff, but I’ve gotten used to it and generally enjoy its sound and build to a high degree.


Included with my unit was a really nice leather case, as well as a monstrous Van Nuys case that can probably hold a DAP and two pairs of IEMs. That may just be for the first few buyers, but either way this is outfitted with some seriously nice gear. You also get a great assortment of tips (Comply, Sedna and UM). While I won’t say this packaging is up the level of something like the VE Erlkonig, it’s a carefully thought out and impressive package that I really enjoyed perusing about.

Mason FS – Fabled Sound or FuSang?

I’m going to put a small blurb on this because by the time I finish writing this review, maybe all 20 units of the first run of Mason Fabled Sound will be all gone. Since I began writing and listening to my Fabulous Sidekick, another version has been released that is called the Mason FuSang. This has identical internals (12 balanced armatures, one bone conduction system) and comes in an acrylic shell and includes a different cable. For all intents and purposes, the sound should be the same on both with minor differences due to the materials and cable. So, I guess what I am getting at, is that hopefully you find this review applicable to both versions and you choose which one suits you best based on price. I went all in YOLO-style when I saw the Fabled Sound hit the MusicTeck website, but would be equally happy with the FuSang.


Test Setup

This part is also boring, but it’s important to know what was used as a testing bed. If it’s a 3.5mm jack out of a mid-range cell phone, I believe results will be different than if a top-tier desktop rig was used. Most of my testing was done on my trusty. Ifi iDSD Pro desktop DAC/amp, utilizing the tube amp setting. This is a very neutral source, even on the tube setting, sort of akin to the Hugo 2. It’s capable of presenting extremely detailed sound and a massive, spacious stage. Additionally, I used my Hiby R8 DAP. For when I. was not at my desk. Source files were played from Tidal HiFi (FLAC or “Masters” aka MQA) and the stock cable was used.

Finally, the Sound

Okay, so here we are. The Mason Freshly Sensational is a very special IEM in the way it produces sound. There are 12 balanced armatures which together cover the whole frequency range, along with a bone conduction system that also covers (and enhances) the full spectrum. The sound signature of the Mason Faithful Star is HiFi neutral/natural to me, meaning there is very little enhancement in any one frequency area. I have not seen a graph of this IEM, but I would guess that it is fairly flat with a faint hint of W-shaped curve. This is a very versatile IEM, yet I think it is best served to music with vocals (more on that later). It covers a wide range of genres and can be an incredible all-rounder, with nuanced and subtle tricks that make music sound sublime. Overall, the sound is absolutely top-of-the-line quality and careful tuning becomes immediately obvious when you place these in your ears. Also worth mentioning, this IEM requires a lot of power. I find that out of all my IEMs, this requires the highest notch on the volume knob.


Let’s go through the range, starting with the bass. The bass is tight, punchy, has a slight bias toward mid-bass where the sub-bass is fairly neutral. The bass on these is miles away (in quantity) from IEMs with a dynamic driver like the Fourte Noir or Noble Sultan, yet they never feel dry or lacking down low in the range. Instead, you get the sense that bass is presented exactly how it is supposed to be presented and accurate to a fault. Sub-bass rumble is neutral as I said, with mid-bass punch being pretty neutral but slightly enhanced. Kick drums, for example, thumb quickly and impactfully, but synthetic rumble from certain sound tracks is on the lighter side. Bass is great overall, but judging it on its own does a disservice to this IEMs overall character. It’s a fine bass, done well in a neutral manner. No complaints, but the rumble will not be knocking your socks off anytime soon.

Mids and Vocals

I joke that I have a difficult time describing mids and always just case for bass and treble, but friends, the mids have arrived! Wow, the female vocals on the Mason Fantastic Singers are simply out of this world and provide a feeling of realism right into your ears. Male vocals do the same, with weight and texture that truly make you feel like you are there at the show. Electric guitar riffs subtly (and sometimes vigorously) tickle your senses and ears with realism that makes you look around the room and wonder. I don’t know if this is the bone conduction system, the masterfully-tuned balanced armatures or both, but these IEMs present the best vocals I have ever heard. The entire mid-range, from lower mids all the way to upper mids, are quite linear but with incredible texture, detail and air. A friend recommended trying “Nightlight” by Illenium to showcase the abilities and seriously, this was an epic experience. Now, I’m not saying the bone conduction system vibrates your ears or anything like that (well maybe it does on a subconscious level), but it absolutely does its job to make things sound just a touch more present and near you. At least, that is my guess on what it is doing and what I am hearing. Anyway, back to the sound, I am incredibly impressed with the mid-range. There is not any feeling of dryness, but the mids are neutral, natural and crystal clear with air and space. They are ever so slightly more forward than the bass, but they are not bathed in warmth or enhanced with any thickness. There’s just so much headroom in here that makes the mids the star of the show, giving absolutely effortless and lifelike sound track after track. The overall technicalities and abilities of the Mason Fascinating Satisfaction with regards to vocals especially has to be heard and experienced; I think it’s pretty much the closest I’m going to get in my lifetime to Dua Lipa whispering sweet nothings in my ear!


The trend these days is estat hardware for the highs, but I am slightly unconvinced of their necessity. I’ve had numerous all-BA IEMs and many estats and I’ll go out on a limb to say the implementation/crossover/tuning is what really matters. So here, we have some beautifully-tuned treble with sparkle and extension that deserves the designation of summit-fi. High hats are incredibly quick and precise, while the highest registers of vocals have a spine-tingling realism and feel. This IEM is not overly-sparkly and I do not see anyone being truly bothered by that sparkle, but it goes up to the highest of highs with an effortless attack that ensues so much air in those frequencies. Again, it’s a nuanced and refined tuning that carefully straddles the line of enhanced sparkle and smoothed treble. It’s perfect (for me, a slight treble-head) and I’m really impressed with what UM have tickled out of “normal” balanced armature drivers. And with the bone conduction system adding texture and feeling to the highs, well, it’s a real high that has to be experienced.

Stage and Separation

Probably the most difficult part of any review for me is describing the dimensions of a stage. Thankfully, I’ve clocked in some serious hours on the Mason Favorite Sauce and am confident enough to say that the stage is a selling point of this IEM. While not as out-of-your-head vast as a competing $6,000 IEM, it’s an adequately spacious, accurate and lifelike perception of stage that still wows on first listen. If I were to describe the dimensions, I would say the width is the star of the show with the height and depth falling in line at a slightly lesser degree. Overall, while listening to live music tracks, it’s very easy to close your eyes and picture the concert as you would experience it, without feeling overly enhanced or out of your head. You’re closer to the musicians than some other IEMs with a massive stage, but everything feels lifelike. Hard to describe really, and I seem to be doing a properly mediocre job of that. Essentially, the Mason Fearless Sound presents music in a way that really makes you feel close to it, rather than testing the distance of just how far that drummer can be off to the left, or that bass guitar off to the right.

Separation on the Mason Fashionably Sassy is above average with impressive depictions of instruments. This IEM is not all about detail, with resolution not being the defining trait. But, it still presents massive amounts of detail, just in an effortless and natural way. Nothing sounds clinical, nothing sounds forced and you won’t find yourself testing whether or not you can hear someone sneeze in the third row. Instead, this is a tuning that takes you past analyzing each sound and lets you enjoy an soundscape that has all the details in the right place. Natural, neutral, very high-resolution and never overdone. It’s impressive and I never tire of listening.


UM Mason V3+
: I loved the V3+ from the day I got it for its natural, smooth sound with sublime layering and texture. It sounded like a big IEM, and needed a lot of power to get the best from it. I’m happy to say that the Mason Follow-up Sound does not stray too far from the V3+, but there are differences worth mentioning. The V3+ has a thicker, warmer tone to it where the latest and greatest goes for ultimate neutrality and realism. V3+ has a big more bass impact, where Fabled Sound goes for speed, clarity and precision. Mid-range is similar tonality-wise, but the Mason Freakin’ Special gives that texture I mentioned earlier where you can feel the singers notes. For vocals, nothing can touch the Mason Fantabulous Singers’ ability to make you feel like you are part of the music. Treble sparkle is enhanced and more extended to my ears on the Fabled Sound, but that may be the smooth tuning of the V3+. Detail-wise, I think I hear a bit more clarity in the latest version of Mason, though V3+ is obviously no slouch. Stage is comparable on the two of them, but perception of being in a live concert goes to Mason Full Stadium due to its magic and unicorn dust in the mids, courtesy of the bone conduction system.


EE Odin: this is an interesting comparison because these monitors are miles apart in technology and sound, yet they’re both going for super high-fidelity neutral tuning to give you ever last ounce of your music with nothing lost. I should note that I’m using the wonderful Effect Audio Code51 cable with the Odin, which adds a touch more resolution and transparency in comparison to the stock PW Audio 1960. With that said, let’s start with the bass: Odin wins here. Whether you’re a bass head, neutral head, whatever head, the bass is just better on the Odin. It hits harder, rumbles deeper and has an incredible sense of texture. The rest, I’m afraid, I think would go to the Mason Frequency Star. Into the mids, the Mason has texture, realism, warmth and timbre that the Odin does not compete with. Odin is a very neutral, dry mid-range that may have a touch more detail, but the Mason really presents mids and vocals in a more effortless way that is less fatiguing and more enjoyable to my ears. Treble is where these two IEMs also differ, with Odin being more precise and sharper while Mason has a denser and more relaxed upper end. It’s hard to tell which has higher extension and I would probably call it a tie, but Odin has been reported to bother treble-sensitive listeners (but I love it and crave that precision). Stage dimensions sound roughly similar to me, where it’s a little hard to judge or declare a winner because of the different tuning nature. Mason Feels Soft in comparison to Odin, where Odin is sometimes too much for a relaxing listen.


Noble Sultan LE: the Sultan LE has been my favorite all-rounder hybrid because of its fun bass with a W-shaped signature. In this test, I paired the Sultan LE with the awesome Eletech Iliad, which takes all of the Sultan’s characteristics and turns them up to 11. The Sultan never does anything wrong, it’s just pure fun with dynamics in spades and an engaging but non-fatiguing listen. The Mason Familiar Secret is a more nuanced, more mature sound that has a lighter touch on everything. That’s not to say there is less body in the Mason Fully Satisfied, but the Sultan is the energetic party animal where Mason is more reserved. Resolution and detail, despite having wildly different tuning, seems to be on-par. Bass on the Sultan LE goes deeper and hits massively harder, where Mason is tighter and quicker as to be expected. Mids, again with Mason Freakishly Special, have a physical touch that no other monitor I’ve heard can compete with. But Sultan is still excellent here and the W-shaped signature really works well for it. The mids and vocals, despite bombastic bass and sparkly treble, are always present thanks to the Wizard’s clever tuning. Into the higher notes, I hear Sultan having a thicker, denser treble (as is consistent with most estats I’ve heard, sans Odin). The Sultan is the more fun of the two, where Mason’s Final Solution is that it gives the best interpretation of vocals/singers that I’ve heard to date.


64 Audio Tia Fourte Noir: of course the Noir has to be included in this comparison, given its musicality, technical prowess, somewhat-cult following and unique sound. That said, these IEMs give the listener quite different experiences and sound signatures, so I’ll declare right now that it’s again hard to pick a “winner” and will depend on what the listener prefers for themselves. Starting with the bass, the Noir has a warm, thick, analogue-sounding dynamic driver kick that is one of the best I’ve heard. Still no Legend X in quantity, but it’s definitely north of neutral. It’s on the slower side, where the quicker attack of the Mason Faster Slam is immediately obvious. Quantity-wise, the Noir has much more bass, both in the sub and mid-bass regions. Into the mids (and acknowledging that the Noir is an improvement over the original Fourte here), the Mason Fancy Specimen has a more lifelike feel and has a greater ability to connect the listener to the vocals. Noir has a nicely textured and warm mid-range, but the Mason vocals shine through clearer and with more air. Into the treble, Noir is hard to compete with given its Tia driver and very high extension. These two are fairly close, with perhaps a very slight edge going to Noir in extension. Mason Frequency Spectrum comes close, with plenty of sparkle and extension and sounding the more natural of the two. Performance is fairly close here and I find myself struggling a bit to find any other differences in the highs, which is a great thing for Mason. Detail and separation is similar on the two, though Noir sounds a little less natural and Mason sounding more effortless in its detail portrayal. It’s hard to believe that just a bit ago, Noir was on the very extreme end of IEM pricing – but Mason Financial Sadness has changed that right quick! Oh and I almost forgot to mention, Noir was paired with a beautiful pure silver cable lovingly crafted by Justin (@doctorjuggles) at Khanyayo Cables.


Oriolus Traillii: I could probably spend a few days just listening to these back to back and I do actually question my own ability to fully report on the differences between these two summit-fi IEMs. But what the hell, let’s give it a go. I promise not to talk about Traillii’s cardboard box anymore as well. The first thing that struck me upon listening to Traillii was an insanely wide stage that extends fully out of your head and into your neighbor’s yard. It’s almost uncanny and is very special in that regard. Once you get over that jaw-dropping stage, you hear an incredibly deep, impactful bass that would make you wonder if there actually is a dynamic driver contained within. Switching over to Mason Feeling Second-best, there are plenty of tricks up its sleeve to not only compete with Traillii, but surpass it in some areas. Stage, while not as insanely wide or deep, gives the sense of being inside the music and actually at the live show thanks to the physicality and texture (likely from the bone conduction system). Dimensions are narrower, but you get a similar grin-inducing feel and immediately know the IEM is special in its own right. Bass is quicker, though less impactful than Traillii and doesn’t extend as deep. Into the mids, the Traillii is very good in its own right with a very clear, natural and airy presentation of vocals. Mason Formally Surpasses in the area of vocals for me, though, with a more bodied sound in the singers’ voices and that texture that I’ve talked so much about (Dua Lipa...whispering...you know...). Traillii is quite balanced, though somehow Mason almost makes the Traillii sound a touch U-shaped given how present the vocals are on the Mason. Into the treble region, damn, this is a tough one. Traillii extends way up into the maximum registers with an effortless air and sparkle that is some of the nicest treble I’ve ever heard. Mason Fresh Shine has incredible sparkle and extension too, but it’s not as effortless and natural as Traillii. Notes up high are a touch thicker, where Traillii is so light on its feet here. Neither will bother treble sensitive listeners in my opinion, because they don’t sound bright at all. It’s treble done perfectly in my book, with Traillii being the airier and sparklier of the two, with a touch more thickness on the Mason. For detail and separation, I really cannot choose a winner here given the different way these IEMs portray the sound. What I will say is this: putting either in your ear gives you the summit-fi experience and both perform so exceptionally well. Traillii might be a “safer” bet because it does nothing wrong, but Mason Fascinating Solution really brings home a special texture and sound. Both come with top of the line cables and both will give you endgame performance several times over. One comes with a cardboard box. Sorry.


Here we are at the end of the review and I’m left with this feeling that I haven’t managed to even scratch the surface of describing what Mason Faithful Soulmate is capable of and I blame my own lack of creativity and writing for that. But at the end of the day, I think it should speak volumes that I spent $6,000 on an IEM and I am pleased with it. And yet, that is the elephant in the room: should anyone actually be crazy enough to spend that on an IEM? Well, let me tell you my justification and you can take it with a grain of salt: I know myself too well, and I know that I will never be happy until I own the best. It’s sick, really, but I am chasing that last ounce of performance and fully acknowledge that it comes at great financial cost.

This IEM brings a lot to the table other than just great detail, stunning looks and top of the line accessories. It brings a realism to vocals that I have not heard on anything else, it brings an immersive experience that has to be heard to be believed. While it does most things exceptionally well, it does vocals the best I’ve heard and some might say that in itself is worth the price of entry. Others may say there is nothing on earth that this IEM can do that would be worth that price of entry, and that’s fine too. At the end of the day, this IEM is absolutely a keeper among my stable of gear and it will be with me for a long time (I hope). Whether you go with the Fabled Sound or the FuSang, you’ll get a unique IEM that exudes quality and engineering, with love and soul installed by Unique Melody. In this segment of the market, Mason Firmly Sits at or near the top depending on your preference.

Huge, huge thanks to Andrew at @MusicTeck for allowing me to reserve serial number 001 of this. I will keep it forever and give it to my son Mason when he is old enough to appreciate it. He will probably wonder why the hell there are thick black wires coming out of it and won’t have a device to plug it into, but those are problems for tomorrow.



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Nice! You covered all the comparisons I was waiting for.
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Bit of a missed opportunity, Colin. You could have ended with ‘Mason Full Stop’ 😉
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what daps you used to test?


500+ Head-Fier
A Wonderful Work of Art
A Wonderful Work of Art—Unique Melody Mason Fabled Sound(FS) Review


Unique Melody is running crazy lately. With the releases of MEST, MEST MKII, 3DT, and now Mason Fabled Sound (and the Fusang). It is undoubtedly one of the most heated IEMs brands now. The application of bone conduction drivers (BCD) is definitely attention-grabbing to us audiophiles and successfully brought this veteran IEMs manufacturer back to life. Based on my experience, Mason FS is a clear step-up of MEST and MKII regarding the utilization of BCD. It is truly something unique, and nothing sounds like it so far. The $6000 price tag is not that approachable to all of us, just like when Traillii was launched. But when considering the exclusiveness and the premium quality, it might worth it. In this review, I will talk in detail about how Mason FS feels and sounds.

Disclaimer: This pair was loaned to me by Andrew from MusicTeck who is a dealer based in NJ. He carries an amazing selection of products including IEMs, portable music players, headphones and cables.

Packaging and Accessory
Mason has decent packaging and accessory sets as always. I want to point out that the leather case from Dignis is terrific, and the quality is extremely high class. The Azla Xelastec tips are always my goto tips for all my IEMs, but the stock black/blue silicone tips sometimes provide me a more open sound when pair with Mason. Overall, I would give Mason’s packaging a solid A, not the most luxurious looking like VE’s but very practical.

The “Attila”

Attila is the custom cable that comes with Mason FS. According to the UM, Attila is specially tuned for Mason FS, manufactured by PWAudio. For its exterior and stand-alone price($1999), I initially guessed it was based on the 1960s 4 wires. Unfortunately, I no longer own the 1960s, but I have the stock cable for Traillii, which is based on 1960s 4 wires. Interestingly enough, I found these two cables are quite different.
The Attila is a bit stiffer than the Traillii’s cable. It may be because the Attila is still relatively new or the inner shielding or core materials are indeed different. Sonically, Attila has a better dynamic, and it also makes the bass to mids sounds more bodied and has a better texture. However, the treble from Attila is not as airy as the Traillii’s cable. Oddly, pairing Attila with Traillii creates a great synergy, even better than the Traillii stock combo, mainly in image and dynamic. Not the other way around, Mason FS with Traillii’s cable makes some flat and dull sounds. Both cables are of TOTL quality, but the Attila is closer to my preference, and in my opinion, the Attila has slightly better quality. (Note: Results were concluded from the tests based on both Mason & Traillii).


Mason FS is the true Unique Melody. It is something that I have never heard before in my life from both IEMs and full-size cans’ camps. However, you can still tell it is from the UM, and it is in Mason’s line-up as it shares a similar reference tuning trend as the previous Mason V3 and V3+. UM further enhanced the term “reference” with Mason FS as it delivers an extremely neutral tonality, a photorealistic texture & image, and a perfect spherical soundstage. It outperforms almost all the IEMs I have heard in technical performance, except Traillii in the soundstage size comparison.

Timbre and Tonality
The timbre of Mason is superb, and I am pretty certain it is the most appealing one I have heard. It is mellow but not soft at all. Every note has an exceptionally well-polished edge, and in the meanwhile being very rich and solid. Nothing harsh or brassy. It also sits in the perfect neutral place between bright and dark. I am completely falling in love with FS’s timbre, and it is the absolute king in the realm of timbre and texture. Surprisingly, I found most of the other TOTL IEMs are pretty far away from the throne, with only a few exceptions like Erlkonig, which is close but still not there.
In terms of tonality, I found FS is on the neutral-warm side. It has some lovely sweet and warm tones but without fuzziness. It mixes the attractive warmth and world-class resolution perfectly. FS also has a slight emphasis on mid-bass, making the overall sound super authoritative and powerful.

As I mentioned above, FS has a slightly emphasized mid-bass. The sub-bass is awesome too, but just not as prominent as the mid-bass. Therefore, the overall bass performance is on the clean, fast, and hard-hitting side, not the warm, rumbly bass. Meanwhile, I found the bass notes from FS are always in precise figures and retain a beautiful physicality throughout the lower frequency. It punches really hard, and I can almost air is squeezed out of the bass drum and hit right in my face.

The signature of FS’s bass is quite versatile. I found it suits perfectly with many genres, and it really shines out with some rock and metal tracks. As I was testing the In Waves from Trivium, FS keeps delivering the fast, clean and punchy drum lines that are heavenly satisfying. Similarly, with funk and instrumental jazz or fusion, FS’s tight and punchy bass makes the tracks sound clean and fluid. For classics, I think it is down to your preference. If you prefer some tight and precise bass, I think FS is spot on, and it is undoubtedly one of the best, if not the best. However, if you are looking for some rich sub-bass and craving bass rumbles, there are some better choices like Thummim.

As much as I wish to hold myself and write an objective review, I can’t while writing this part.
Like lots of the users have declared in the forum. Mason is the Mid King. However, I don’t think UM engineers have added extra spices to the mids, but they amazingly utilized the bone conduction system on the Mason FS. To me, it is again the uncannily beautiful texture and timbre that play a critical role here. The mids and vocals from FS are not upfront or sit backward. They are again at the almost perfect “reference” position, which sounds very natural to me. Now, here is the magic, the mids and vocals from Mason are incredibly life-like. As mids are the most familiar ranges to most of us, you will be more likely to have an “emotional echo” with FS’s mids. I have tested so many vocals from both females and males. I also tried lots of mids-centric acoustic guitar and piano tracks, all of them sound insanely well. There are no artificial flavors added to this beautiful mids, but the natural, pure sounds constantly hold my breath.

If I have to pick my least favorite parts from Mason FS, it would be the treble. However, by no means, Mason’s treble is bad. To my ears, the treble from Mason is silky smooth with nothing harsh or raspy. Meanwhile, the treble extends very high and creates some decent air. I can feel that UM is trying to tune the treble of Mason to be “flawless”, but to me, the biggest flaw of Mason's treble is being “flawless”. I always wanted some sparkles or even some edges to add excitement to the music, but that cannot be found from Mason without EQ. It is not very noticeable of lacking excitement while playing vocals or classics, but it is pretty apparent for cymbals heavy tracks such as Metal.

Soundstage and Image
The soundstage of Mason FS is perfectly spherical. You can quickly get a holographic “vision” once you plug them in. With the bone conduction system, you will also get an immersive feel which you can rarely find in a personal audio system, IEMs, headphones, 2.1 speakers, all included. MEST MKII has already given me that sense, but Mason FS is providing me the grown-up feelings. Mason FS will lead you to the stage where the instruments and singers are surrounding you. You can have the sounds from the top/ bottom, left/ right, front/back, and you are coated by the music.
The images are one of the most accurate and natural images that I have got from the IEMs. The images are not too far nor too close, and meanwhile, it has completely no compromise in size and thickness. All notes retain exact precise figures from bass to treble. Combined with the soundstage signature, Mason FS creates the most photorealistic images I have ever heard. However, due to the excellent thickness and fullness in imaging, Mason FS is not the most spacious and open-sounding IEMs. Mason FS perfectly mingles the involving and resolving natures of the high-end audio gears.

For all the IEMs I have heard, the bird Traillii is the only one that comes close to Mason FS and worth comparing. And it is quite interesting comparing “ The Wood” versus “ The Bird”.

Design & Fit
Mason FS offers prestige stabilized Cholla shells coated by blue resin that look absolutely stunning and unique. The shells are slightly on the larger side especially come to the nozzles. Fortunately, they are not making any trouble to my medium size ears. As a reference, VE Erlkonig is the largest shape I can bear, and FS is more ergonomic than VE and fits me better.
Traillii offers custom faceplates. The default shell design is classic but not outstanding. The design is outperformed by Mason in the side-by-side comparison. The build quality is very close to Mason, but I would still give the edge to the Wood. However, the fitting is better on Traillii, the Bird has thinner nozzles, and I think it is slightly lighter than Mason.

Packaging and Accessories
Hands down, Mason is the clear winner. Compared to the closefisted Oriolus, UM offers way better packaging and a lot more accessories. Mason comes with a more excellent hard case than the generic 50 cents parper case that comes with Traillii. Mason also has one of the most premium leather carrying cases from Dignis that is aesthetically beautiful and practically durable. Meanwhile, Mason comes with 3 sets of tips: Azla Xelastec tips (S/MS/M), Comply foam tips, and the house custom black silicone tips. All three tips are excellent in quality. Oh, also, the small magnetic shirt clip is a lot more useful than you would expect. Plus, Musicteck is offering a similar and better/larger (than Traillii’s) VN case as a bonus.

Both Mason and Traillii are easy to drive. I found Traillii is less picky about the source and slightly easier to drive. Mason is not hard to drive, but it is very fastidious about the source.
Due to the fact that Mason is having a reference and slightly flat sound signature, the less dynamic/gentle tuned AK devices are not ideal with FS. Things like R2R DAPs and tube amps are giving some nice flavors to the Mason. DAP like R8 that provides an excellent dynamic and a decent EQ system is not bad for Mason as well. With better DAC and AMPs, Mason FS can noticeably stack up. On my desktop setup (Bricasti M1SE + Cayin HA300), Mason sounds speechlessly amazing despite there is a noise floor from the 8W tube amp, lol.

Traillii, on the other hand, is more source-friendly. It will have great synergies with the major high-end DAPs that are currently in the market. The only thing you might need to care about when selecting the source for Traillii is the “control” in sound. With some external amps, the Traillii can sound shouty and less natural. But still, I found Traillii is a lot easier to the sources.


Having both Mason and Traillii is just the end of the game, no more searching and no more wrangling. Both of them are amazing, but they are very different and almost antipodal in tuning ideology.
In the overall signature, Mason focuses more on texture and tactility. It has wonderful microdynamics that can send the tiniest vibration changes to your ears. It sounds incredibly natural and realistic but unique too. Overall, it is more artistic and authoritative than Traillii in terms of tuning.

Traillii, on the other hand, sounds more open and buzzy. It is emotional and always energetic. It is the most open-sounding IEMs I have listened to so far. The soundstage is simply excellent from Traillii. It has the most expansive stage from and IEMs, and you can hear all the details are flying around you. So, in my opinion, Traillii has a more attention-grabbing tuning than Mason.

In the bass, Mason has the emphasis on mid-bass. It is fast, clean and punchy. Traillii has more sub-bass rumbles and sounds more linear. In mids, Mason has the unique tactility which nothing can come even close. Traillii’s mid is not bad, but compare to Mason, it is generic, and I won’t be surprised that you can find a similar or even better mids than Traillii’s at a lower price range. But you can never find the mid-frequency from any other IEMs that are similar to Mason, period. Traillii’s treble shines out! It is sparkling, airy, and full of energy. It always catches my attention while listening to them. Mason’s treble is slightly darker than Traillii, a little less sparkling, and less energetic. But Mason’s treble is even smoother and more natural than Traillii. It is the smoothest treble and sounds very mature and well polished.

So, in conclusion, Traillii is the King of Mainstream IEMs. You might hear many IEMs similar to Traillii, but no one is tuned as well as Traillii in that genre. Mason is the leader of a revolution, and it truly opened up a new feel of the sound. It brought the sound with one extra dimension. Nothing comes close to Mason in terms of sound signature, and it is still tuned beautifully with all the high-end performance you are expecting.

Final Verdict
Mason is crazy. I still find myself wordless in describing how it sounds. Mason FS is for sure the groundbreaker to the industry with the fantastic utilization of bone conduction drivers. It added tactility to the sound, which has never been done before. Even the in-house MEST MKII is not close in terms of the “bone conduction effect”. As a $6000 MSRP IEMs, by no means I should say it is a bargain. But for the uniqueness, exclusiveness, and awesomeness of Mason FS in sound and design, I think it is definitely worth the price tag. Ultimately, you are getting the finest made audio gear with an exclusive sound signature and technical performance that can never be found elsewhere.
I wonder how the Mason FS compares to full-size headphones at the similar price range:L3000:
With all musical genres, does Trailli and Mason always announce themselves the same way?
In the sense ... neither of them loses her character? Between Trailli and Mason which of the two remains more versatile?
They look pretty, but the lack of customisation seems very short-sighted, when these companies are making out they are the best. Very focused on the internals, then a one-size-fits-all (literally) exterior. I used to be a heavy user of earbuds but with anyone's ear resin is going to rub and ache after a while. Why no ear moulds? Why no silicone even? Seems like just trying to make money off people without much actual effort in the manufacturing.

bigbeans' review pointed out that bone conduction will not work for EDM or synthetic music, but the real issue I think is that there's a lot of stuff online saying bone conduction can cause noise-induced hearing loss (NIHL) or permanent tinnitus since it directly "attacks" the cochlea's stereocilia