UM MEXT Review

I feel really lucky that I’ve been able to review more IEMs in the $1k range as of late. My go to IEM is the THIEAUDIO Clairvoyance($700) and I’m always looking for something that impresses me enough to move to a post $1k IEM. The Symphonium Helios has been the closest to get me there but I don’t find them very attractive nor super comfortable for long term listening. The UM brand is new to me in terms of experience but I have eyeballed their IEMS that range from $319 all the way to $8400 dollars which is mind boggling to me. I always wanted to try the original MEST but never had time to audition them when a local friend had them for a bit. So this will be my first UM product review. The MEXT is using a single dynamic driver for the lows, an in house bone conductor(OBC) for mids/treble and finally 4 BA drivers mixed in. The UM MEXT comes in at $1200.

Quick shoutout to both Unique Melody for offering a MEXT to review and Andrew from Musicteck for sacrificing a unit from his inventory for me to test and review. While I always appreciate the chance to test and review products sent in from manufacturers, it never affects the rating of my reviews.

Gear Used

IPhone 12 pro with headphone adapter, Aune BU2, iFi Go blu, Hiby R6 2020 and SMSL SU-9 feeding the SP400 amp.

Looks and fit

The shell is a little bigger with a thicker nozzle but I didn’t have any issues with comfort and when paired with the stock AZLA tips that come on the MEXT, I had really good long term comfort. I can easily get lost in multi hour listening sessions and these were fantastic for those moments comfort wise. The faceplate is a little boring with the gold UM logo and whatever flower plant logo thing they’re using but it's simple and comfy so it gets a pass from me. It also has a nice design at the bottom of each shell to tell you where the bone conductor driver is.

Isolation and sound leakage

The passive isolation is ok but since this is a hybrid, it has two venting ports to help the single DD perform well. This meant that I didn’t need to really take out my IEMs if someone was talking since I could mostly make out what they said but it wasn’t as good as a set of sealed BA only IEMs. It doesn’t leak much sound which I was surprised about being a hybrid with two vents on each shell. I still wouldn’t listen to these at full volume on say a plane or in a super quiet room but at lower volumes, no one will hear what you’re listening to.

Packaging and accessories

I really like the presentation when it comes to the packaging. It's a simple and smaller box with a flip cover. Inside is a nice teal UM branded leather storage case which has the MEXT and cable inside. It also has a divider should you wish to separate each IEM shell. The box also has a pull out drawer which includes all the other accessories. We get the silicone tips in a nice little container, the warranty card with serial number, a set of extra small to medium AZLA Xelastec tips, a cleaning cloth and replacement nozzle filters. I think this is a good set of accessories.


These final impressions were done off a mix of the iFi GO blu, Hiby R6 2020 and the SMSL SU-9 connected to the SMSL SP400. These are what the MEXT sounded like to my ears. This was also using the stock Xelastec eartips from AZLA. Things like ear tip selection and DAC/amp selection will produce different results and impressions vs what my ears hear on my specific gear.

When it comes to hybrids, I almost always expect really good DD bass and the MEXT does bass really well. I was expecting these to be bass cannons due to the bone conductor but instead it's a slightly boosted bass with well detailed lows. The MEXT is able to reach down low and it’s able to produce great impact and slam when called for. This won’t be a bass head’s dream IEM but I think it does really good bass and that plays into the bone conductor and mid bass. Speaking of the mid bass, I think that's where the star of the show starts. Something about the mid bass is really good. I don’t like boosted midbass and lacking sub bass. The MEXT does good sub bass and really good mid bass. It blends really well and makes for some really airy bass that is never too strong nor lean. The mids are done really well here overall, I found instruments come in clear and vocals come in fairly detailed but with a slight twist. The mids and lower treble have a slight echo which has a neat effect. There is a little extra “echo” or a longer decay that gives everything just the smallest additional flavor. This gave vocals a slightly livelier sound. It’s not overpowering and just slightly noticeable but it was probably the very first thing I noticed on first listen. The treble is done pretty well here. It’s not nearly as good detail wise as something like the Symphonium Helios I reviewed recently but I find it to bring in better details than my trusty Clairvoyance. It still sounds a little tame to my ears but in a “I’m not going to be murdered by brightness” kinda way. There isn’t quite the extra sharpness or zing at the end of higher pitched instruments but as someone who gets iffy about details in drums, I found things like various cymbal notes to come in really well just missing a little bite at the end of the notes. I really like the tuning overall on the MEXT and this is probably the first IEM in a bit since the Clairvoyance that has me completely hooked in terms of an overall fit, comfort and tuning.

Bone conductor testing

So the bone conductor claims to work between 200-7000 kHz. I used a simple online tone generator to see when I could feel the shell start to vibrate with my finger while it was in my ear. I started getting feedback via touch between 210 Hz to about 5200 kHz where I can’t really feel anything. Between 315 Hz to 430 Hz was the most intense the feedback gets. While I wouldn’t say it did anything life changing, I did on occasion notice certain instruments that would “ping” or give my ear light touch. It doesn’t happen often at all but I can reproduce it on some songs. It’s neat for the once in a blue moon experience but I don’t think the OBC from UM makes a big difference other than the echo/decay I mentioned above in my sound preferences.


Staging is above average width wise but the depth and height are really good. Whether it’s the OBC driver adding the longer decay or just good tuning, the stage feels really big for an IEM. This isn’t close to any open back full size headphone but I really like whatever is going on with the staging. Imaging is fairly good but with the extra decay, I feel like things can get a little cluttered when too much is going on all at once. When things are more dialed in, the imaging is fantastic and I was able to really pick out exactly where sounds were coming from in the bigger soundstage. 


The MEXT isn’t super hard to drive but it does like a little power from what I can tell. The entry level gear such as the Shanling M3X DAP, iFi GO Blu and AUNE BU2 produced good sound but once I moved up to the Hiby R6 2020 and my SMSL desktop stack, the MEXT really came alive. The MEXT isn’t very sensitive but I was still able to pick up a light hiss off the iFi GO Blu via balanced.

Stock cable

I usually cable roll if I think the stock cable is bad or isn’t balanced. I really like the feel and design of the included stock cable. It’s a collab with PW Audio and it has a nice thickness and lightness to it. It had that slightly shiny black rubber finish much like the Audeze cables. The split, jack and connector housings all have a nice matte black paint with a really high quality feel. It doesn’t come with swappable plugs like a lot of IEM cables these days but I didn’t mind as they give a option to choose between 3.5mm, 2.5mm and 4.4mm Pentaconn when you purchase the MEXT. I wish other manufacturers would give these options for their higher end IEMs as most just come with a 3.5mm cable and no options to upgrade or change plugs. The connectors are super tight and it was somewhat difficult to remove the cables from the shells. This is nice(assuming nothing breaks) cause I have a few IEMs that easily detach their 2 pin cable easily if any force is applied.


Tip rolling

I did some tip rolling but quickly settled on the stock AZLA Xelastec tips. I usually don’t like dealing with the Xelastec tips since they have a big positive in negative with their design. The positive is that they’re super grippy and eventually form to the inside of your ear from use and become a semi custom eartip. The drawback is that you can’t really use the same tips on something else and either have to reform the tips or use another set of tips and a two pack goes for a whopping $30 dollars which still blows my mind. I did try my two favorite spinfit tips which were the CP100 Plus and the CP145. Both those tips ended up making the upper mids a little too spicy for my tastes and I just didn’t like the way the tuning sounded overall. I did play with the included silicone tips and once again, I just didn’t quite get the sound I got with the Xelastec tips. I always recommend tip rolling as it usually makes a difference it tuning but I think if you can get the Xelastec tips to fit, stick with those. 

Nozzle filters

There is an extra set of metal filter grills that can be swapped. I appreciate that they include it but the thing I really like is that the filter can be unscrewed and cleaned. While I don’t have heavy wax buildup and I clean my ears every few days, I get some of my IEMs back from friends that are in rough shape and a nightmare to clean their gross ear wax out of. Recently I had to clean the DUNU Falcon Pro of gross ear wax buildup from a friend at work who borrowed it and it was simple to clean since the nozzle was able to be unscrewed. I hope to see more companies do removable metal filters to make cleaning easier. 

IEM comparisons

Symphonium Helios

I don’t have a Helios on hand anymore so this is coming from memory but the Helios is still fresh on the mind so keep that in mind when it comes to this comparison. The helios had a better treble with more detail and just a little extra energy up top vs the MEXT. The MEXT wins in lows and mids however and it has a better soundstage when going off memory. I really liked the Helios and I really like the MEXT. I think both are wonderful options for around the same price. I would grab the Helios for that extreme detail retrieval and neat backwards imaging. The MEXT will be better for those looking for a better soundstage and better lows/mids.

THIEAUDIO Clairvoyance

The Clairs are my favorite and I’m conflicted between those and the MEXT. I think the treble is done a little better and the Clairs present a more clear but dynamic sound compared to the MEXT. The MEXT wins hands down with soundstage and imaging, plus it has more personality when it comes to the tuning and especially vocals. I still love the Clairvoyance but the MEXT is my preferred tuning at the moment. The comfort is way better for me on the MEXT over the Clairs as well. The Helios is a direct upgrade from the Clairs to me so I wouldn’t say buy the MEXT to replace the Clairvoyance for those wondering about upgrading. Get the MEXT to experience something with a little more character to the sound. Grab the Clairs if you want a super clean “all rounder”.

Moondrop Variations

The Variations come in more than half the price of the MEXT but it’s actually the closest thing in tuning I have on hand. The Variations have a way more powerful/focus on the bass with ok mids and a slightly spicier treble. The MEXT feels like an upgraded Variations with the really good lows, really good mids and controlled and detailed yet less sharp highs in comparison. Both IEMs have a well done and wide soundstage with a better sense of space. I kinda want to call the Variations a baby MEXT but more raw and less defined. Both are good and my daily rotation of IEMs for work includes the Variations so I still like them even when I have the MEXT on hand.

Amping Combinations

iFi GO Blu

The GO Blue was able to give the MEXT enough juice to sound fine but it didn’t quite give enough energy to really open the sound. I usually like the GO Blu for all my IEMs but this was a rare time I really noticed an IEM being picking when paired to the GO Blu. The xBASS didn’t add much subass. The xSPACE didn’t really add much top end energy either. The hiss was light with xSpace off while being run balanced but with the xSPACE turned on, it was a rough hiss and I opted to run the pairing stock with no iFi hardware EQ. This was a good combo but I would try and opt for something a little more powerful if possible.

HIBY R6 2020

When comparing the R6 2020 to a desktop amp for IEMs, I think it's worth the price that the R6 comes in at. I like the warmer sound of the DAP and it does well at powering the MEXT properly. I mentioned above that the MEXT does well off more powerful sources and it really showed on the R6 2020. I had a lot of the extra staging and better tuning quality I got from the larger desktop stack I use. I would absolutely recommend the pairing. 


This is the main desktop setup I use to review all my gear since I got the “stack” a while back. The biggest differences besides the wider soundstage would have to be the control and speed. The bass was more detailed and controlled, things sounded quick and the longer decay is controlled and less of a mess when things get congested. The vocals had a little extra life to them and the treble was well detailed though the SU-9 DAC in this stack doesn’t do much sharpness up top so it didn’t ever sound too bright or piercing. I think a good quality DAC and amp will help the MEXT perform its best.

Overall thoughts

I was really impressed with the MEXT and in all honesty I wasn’t sure what to expect at first. I had figured I would be getting a bass cannon with the bone conductor being a thing but I didn’t start looking into the use of the OBC until after I had my first listen. While I like most new audio gear on first listen it can definitely fade after some time. This was one of the few IEMs like the Helios I recently reviewed that I stayed hooked on well after the honeymoon phase passed. I absolutely recommend the MEXT if you want something with a little extra personality but still acts as a good “all rounder”. I had a great time with the MEXT and look forward to checking out more UM offerings down the road. Great job to the team with the release of the MEXT! Thanks for reading!

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