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Westone UM 50 Pro Review – A Flagship with Heart

Introduction –

Westone separate their universal range of iems into two categories, the consumer W series and the more professionally orientated UM Pro series that were designed for use during live performances. This is a very different usage case scenario than something like a studio monitor, and as such, the UM line pursue a more powerful, less fatiguing sound that is designed to be listened to in a loud environment for prolonged periods of time. Whilst Westone`s W line holds the spotlight for most users, the UM Pro line retains a smaller, yet more loyal following and for good reason, the UM 50 Pro`s hold many key advantages over my previous W30`s and even the W40`s.

With a $650 USD RRP, the UM 50 Pro`s aren`t cheap, but the combination of proprietary drivers, supreme ergonomics and a very interesting sound produce a product that might just be worth your while.


About Me – Some background, Gear of choice, Preferences and Biases

I generally prefer a slight v-shape to my sound, but still closer to neutral. I like a lot of detail and clarity, but can appreciate a smooth, laid back sound such as that on the X10`s. I prefer a more neutral midrange within a relatively tight tolerance, but I`m probably more forgiving of brightness over darkness. I`m not particularly treble sensitive and can tolerate large amounts without fatigue, though too much ruins the enjoyment. If I use a different eartip/pad/cover during the review I will note that and describe the sound changes.

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Accessories –

The UM 50 pro`s come within the typical Westone box that presents the earphones and model number on the front, a few specs on the back and some warranty information on the side.

Like the W30`s, this outer sheath slides open to reveal a rubberized hard case with a pull tab that opens the magnetic flap. A foam inlet encases the earphones and vault case, though I was a bit disappointed that the UM 50`s didn`t come with the new frosted case with shock absorbers, but the older first gen case instead.

The UM 50 Pro comes bundled with the usual array of accessories, which is a great thing, because Westone provides one of the most comprehensive selections of accessories in the iem world.


Opening up the included carrying case reveals a very generous selection of Star Tips, one pair of medium short silicone tips on the earphones themselves, two pairs of short silicone and foam tips (S,L) and three pairs of long silicone tips and foams (S,M,L). There`s no screw driver here since the UM line lack the swappable face plates of the consumer W series. Another difference, is that Westone only provides buyers with one cable, an EPIC cable with heatshrink ear guides. Since the UM 50 Pro was intended for professional stage use, it does not come with the MFI remote cable that`s included with the W range.


Design –

Unlike the W range, the UM Pro line of iems are built in the USA, a proud selling point for Westone. I personally didn`t notice a huge difference in the actual build quality of the housings on the UM 50 Pro`s as opposed to the W30`s, but the design itself is a lot more pragmatic.


Gone are the bulky, crack-prone faceplate swapping mechanisms of the W range and so far, Westone seem to have alleviated the intermittent MMCX issue as well. Westone`s current generation iems all utilize the popular MMCX connector, but Westone`s connectors are slightly shorter than the average plug. This translated to a somewhat loose connection on my W30`s (especially so with after-market cables) and thus intermittent audio. The UM 50 Pro`s seem to have been built to tighter tolerances because all of my MMCX cables fit much more snugly.


The stock cables have a rock solid connection and aftermarket cables aren`t too loose either, making them a more viable alternative without the use of Deoxit. This is a really nice fix and audio has remained stable even during runs, performances and general motion. I haven`t had it cut out once.


The lack of connector jostle may also be aided by the more stable fit offered by the UM 50 Pro. As mentioned in my W30 review, I much prefer the ergonomics of the UM Pro line to the W line; the housings are smaller, more streamlined and most importantly for me, much slimmer. Although the UM 50 Pro`s contain a staggering 5 balanced armature drivers, they utilize the exact same housings as the triple driver UM 30 Pro`s; they are slightly smaller than the Shure Se535`s for example, mainly they`re a little shorter. They`re also similar in size to the SE215`s, but are a bit thicker, good job Westone.

SE215 – UM 50 Pro

The W30`s had a little extra bulk around the inner surface due to the faceplate mechanism that allowed the earphones to jostle in my ear, eventually losing seal, whilst the UM 50 Pro`s lie completely flush, minimising wind noise and even allowing me to sleep comfortably on my side. They remain completely stable no matter how vigorously I move. This is aided by the lightweight housings and cable, which combined with the ergonomic shape, allows the earphones to disappear over time, forming no hotspots. Of course, you feel the strong sense of suction provided by the sealed iems, but Westone have really nailed the ergonomics of their UM line.

As a result of the more streamlined housings, the UM 50 Pro`s sit a little deeper in my ear than the W30`s and as a result, isolate absolutely brilliantly; you will not find much better isolation from a universal. When wearing the UM 50 Pro`s, even on some of Sydney`s more ancient trains, background noise of all frequencies is effectively attenuated and music is delivered rich and clear. I`m a low level listener, I rarely listen above 3 volume notches on my iPod Touch 4 and HTC M8 for example, making this all the more impressive.


As I stated in my W30 review, the Westone EPIC cable is very nice, well relieved and ergonomic. I much prefer the style of ear guide employed by Westone`s cables to the memory wire used by other brands. The EPIC cable is very light, perfect for use during activity, but it is slightly thin. It`s also lacks the super supple feel of something like the Shozy Cygnus cable, which is possibly the best I`ve experienced. Luckily, the EPIC cable has a very smooth texture and still feels quite solid in tension, it doesn`t grab on clothing nor does it transmit much microphonic noise. The right angle jack and y-split are both well moulded and low profile, the plug will comfortably fit within most cases and is gold plated to prevent crackle.


So whilst the UM 50 Pro lacks the vibrant, customizable looks of the W line, it`s design still invokes a sense of intrigue in its own way. The frosted, semi-transparent outer faces tease the audio prowess of the multi armatures inside while the clear inner face is perfectly smoothed off for ergonomics whilst allowing the intricate internals to peak through. Sure, the UM 50 Pro is not as catching as the Shure se846, but its design looks delightfully understated and just a little technical. The cable is also a LOT more practical than that offered by Shure`s models.

Sound –

As mentioned in the introduction, the UM Pro line were designed mainly for live stage performances, epitomizing the full-bodied Westone house sound users have come to love from the W series. Utilizing 5 balanced armature drivers and a 3 way passive crossover (not stated which drivers are dedicated to what frequencies), the UM 50 Pro sits at the pinnacle of Westone`s UM Pro lineup. I`ve read that the UM 50 Pro is a universal variant of Westone`s ES50 custom and whilst I have no personal experience with this model, those who take a liking to its sound will surely be interested in the UM 50 Pro.

As far as the signature is concerned, the sound is somewhat V-shaped, with an emphasized bass response sitting above a slightly recessed midrange and a generally neutral treble response. It`s similar to Westone`s high end W series iems, but thicker, more textured and laid back. This atypical ba sound is achieved through proprietary, in house designed drivers, setting the UM 50 Pro apart from most other earphones that use a variant of some Knowles driver. This sound includes an amazing sub-bass response that rivals the se846 and some dynamic driver earphones, powerful mid and upper bass responses and a lush lower midrange combined with a crisp upper midrange and high-end. The UM 50 Pro also solves the main gripe I had with the W30`s sound, the soundstage. Given its intended uses, I wouldn`t expect the UM 50 Pro to have a particularly standout soundstage, but in my experiences it sounds very spacious, especially considering the level of seal the iems produce. It`s not quite as large as my ie800`s, but instruments still have great separation; each frequency range is well isolated with its own space. Imaging gets a special mention; the UM 50 Pro`s have pin point precision when it comes to instrument placement and soundstage width in particular is very impressive as well. Listening to a few acoustic tracks, vocals are front and centre whilst guitars and other instruments radiate from the sides, somewhat imitating my 5.1 home theatre system.

The UM 50 Pro`s have a very high sensitivity of 115dB and a moderate 45ohm impedance. While the UM 50 Pro`s will reach ear-splitting volumes from almost any source, I did find them harder to drive than conventional monitors. My iPod nano 7 drove them to very high volumes for example, but quality loss was evident. Meanwhile, my HTC m8 served them with ease, albeit with a strong hiss (more on that later). Despite having such an intricate driver setup, the UM 50 Pro`s didn`t seem to be overly affected by output impedance, sounding almost identical from all of my sources apart from my laptop which struggled a bit with their higher impedance. They are quite hiss prone, not Shure level, but they still pick up a very faint hiss from even my quietest sources. It`s mostly inaudible once the music starts playing but noisier sources such as my HTC m8 are quite prominent, almost intrusive.

Bass –

The UM 50 Pro`s have a large boost to the low end, larger than my ie800`s in everything but sub-bass and larger than the W30`s in everything but mid-bass. The bass response is the most prominent range of the sound on a whole, but it`s impeccably tuned and of immense quality. Personally I find the low end to be a little too strong, but it provides a larger than life listen and the outright quality present cannot be denied. Despite this strong emphasis, the bass is especially revealing, picking up distortion on low quality files a little too easily (the bass response itself is not distorted at all).

The first thing I noticed when listening to the UM 50 Pro was its extremely textured bass response, perhaps more so than my ie800`s which is no small feat. Notes have incredible definition and whilst they lack the punch of the very agile ie800`s, the UM 50 Pro has no difficulties reproducing complex passages with plenty of PRAT, detail and separation between notes. This is strange because the UM 50 Pro`s have a larger bass boost than the W30`s which sometimes get a little lost; perhaps it`s because the UM 50 Pro`s have a more linear boost, sounding full instead of tubby (mid-bass is somewhat balanced with the upper and lower bass responses). The sub-bass on the UM 50 Pro`s is also very impressive. It`s remarkably extended for a ba earphone; the se846`s and dynamic ie800`s will both edge out the UM 50 Pro`s, but they`re very close, lacking only the lowest of lows. The full sub-bass response of the UM 50`s is particularly satisfying during acoustic tracks with great timbre and impact, un-matched by any other micro driver or ba earphone I`ve tested apart from the models aforementioned.

Mid-bass is a little more recessed than the sub and upper bass responses, preventing that bloated, tubby sound. This grants the bass response a sort of hyper defined quality, perhaps also contributing to its sense of perceived prominence. The mid-bass response is still full, just less so than the rest of the bass.

The upper-bass response is somewhat unconventional for a flagship iem. Unlike the ie800`s which actually have a small recess in the upper-bass, the UM 50 Pro`s have quite a large emphasis. This robs them of that ultra-clear, super punchy sound, instead granting the earphones a great sense of lushness. I did find the Upper bass response to encroach slightly upon the lower midrange, losing a small amount of detail, but the bass response of the UM 50 Pro is still very impressive for a sealed, balanced armature earphone. Notably, the linear, slightly sub and upper bass weighted boost creates the impression of a larger or “epic” sound for lack of better vernacular. The low end is still tasteful enough for almost every genre and, in combination with the large soundstage, the UM 50 Pro`s excel with movies and games too.

Mids –

If I had to summarize the most notable features of the midrange in just a handful of words, I would probably choose refined, detailed and smooth. In fact, I wouldn`t hesitate to say that the UM 50 Pro has the smoothest, most refined midrange I`ve ever heard from any earphone.

The UM 50 Pro`s have a thick lower midrange that`s right on the periphery of my tastes. It sounds full-bodied rather than muffled, but that last bit of detail and definition is lost. Male vocals are not as forward as they are on the W30`s, but are rather slightly behind the increased bass response. The lower midrange has a nice sense of presence and the lushness generated by the upper-bass response grants vocals an ethereal quality. Vocals are well layered and the extra crispness in the upper midrange balances out the lower midrange warmth. Despite technically being on the darker side, I didn`t find the upper midrange to sound dull at all, female vocals and instruments inhabiting this frequency range don`t have that scooped sound I got from the W30`s. In addition, the midrange is hyper detailed if not extremely clear. The unbeatable clarity of the ie800`s tends to bring details and intricacies to the fore, but the UM 50 Pro`s are just as proficient, they just aren`t as aggressive. It`s quite a strange phenomenon, but you don`t miss anything in the midrange, the UM 50 Pro`s permeate a supreme sense of refinement.

Compared to the W30`s, the UM 50 Pro`s manage to be both smoother and similarly, if not more revealing. They are pretty much on par with the ie800`s in terms of detail retrieval, but the upper-bass/lower midrange does prove excessive at times. They aren`t remotely bright sounding, but clarity never feels lacking either, even coming from brighter earphones such as the Sennheisers.

Treble –

The treble response on the UM 50 Pro`s is just about neutral. They are devoid of roll-off and the treble response is absolutely extended. The upper midrange transitions well into the high end response, sounding smooth and seamless whilst retaining a sense of separation. In terms of signature, it`s actually sculpted similarly to that on the ie800`s, also resolving similar amounts of detail as well, but it`s nowhere near as emphasized. This might sound like a negative, but it`s actually makes for a very satisfying listen. The UM 50 Pro`s almost have the detail and resolution of the Sennheisers without that splashy character. They sound much less fatiguing as a result, but also less vivid and clear. Regardless, treble has nice texture and just about perfect body.


Verdict –

The UM 50 Pro`s aren`t cheap, I actually paid more for them than my ie800`s. You might be wondering how earphones such as this still have a place on the market when Chinese earphones such as the $350 Dunu DN2000j resolve similar amounts of detail and the even cheaper Shozy Zero boasts a masterfully sculpted sound similar to that on the UM 50 Pro. But I would argue that the extra funds allow for a fantastic ergonomic build made to tight tolerance in the USA, top notch passive noise isolation, a myriad of accessories and, perhaps most importantly, subtlety.


With the influx of hyrbids and loud proprietary technology, manufacturers have lost subtlety, and with subtlety comes refinement. All the ingredients can be present, but it`s the way they`re brought together that grants them this quality; a quality that isn`t forward, aggressive or artificial, but rather encapsulates that quality of simply existing. With manufacturers twisting the dials to 11, the Westone UM 50 Pro`s sit happily at a perfect 10.


Accessories – 9/10, The UM 50 Pro`s come with plenty of tips, a very nice case and a well-built cable. You won`t struggle to find the perfect tip within the included kit.

Design – 10/10, The ergonomics of the UM 50 Pro`s is phenomenal considering that they managed to stuff 5 drivers within each housing. They are smooth, well finished and built to tight tolerances. The look is understated but still catches the eye in a more professional manner.  Westone`s EPIC cable has always been a strong point, and it`s no different here, so far the MMCX connectors seem to be behaving as well. Overall, the UM 50 Pro`s look and feel like a flagship earphone.

Bass – 9/10, Very extended for a BA earphone, great slam and punch without bloat. Phenomenal texturing and detail to each bass note but too much emphasis for home usage. On the go or on the stage as intended, the earphones sound fine however.

Mids – 8.75/10, A little too thick in the lower mids causing a slight detail loss, but upper mids are crisp and clear. Copious detail retrieval just falls short of more aggressive TWFK earphones and the ie800`s, but resolution and detail are amazing considering the powerful sound emitted by the UM 50 Pro`s. Slightly dark but not scooped sounding, vocals sound great.

Highs – 9.75/10, Very resolving and hyper detailed, a little less so than the ie800`s, but they also have more accurate body and texture to the notes. Neutral quantity is unfatiguing and avoids any sibilance.

Soundstage, Imaging and Seperation – 7.75/10, Amazing sense of space considering the design and level of seal. Imaging is perfect and width in particular is great. Separation falls short of the very best earphones on the market somewhat due to the thick sound signature which tends to sound less open. The soundstage is very impressive overall, really proving the earphone`s flagship status.

Overall – 9/10, I understand that the UM 50 Pro`s are not a typical sounding earphone and many probably won`t like the way they sound at all. They are also NOT the ideal upgrade to the W30 and W40 due to the differences in sound signature though it is a sound that presents certain merits. It`s a very unique experience and something that was specifically tuned for a specific function. Despite this, the UM 50 Pro`s have certain additional strengths that make them very suitable for other purposes such as general listening enjoyment. They are versatile in both sound and design, comfort is fantastic and the kit provided with the earphones guarantees a proper fit. If you`re looking for a larger than life listen, then you`d have a hard time topping the UM 50 Pro`s, their outright sound quality is without fault.


12 thoughts on “Westone UM 50 Pro Review – A Flagship with Heart Leave a comment

  1. Слушаю um 50 уже год.Нашел к ним идеальные спутники,bluwave Get и ibasso cb 13.Get имеет мультибитный цап и хороший усилитель,а cb 13 добавил высокие частоты.


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