A MEST have sequel?

PROS: quadbrid driver design (DD/4BA/4EST/BCD) with updated Bone Conduction driver, balanced sound sig with a detailed natural tonality, new Fruitwood faceplates, new PWA shielding OCC copper cable, new custom eartips and accessories, available in Uni and CIEM.

CONS: higher price than Mest MK2, the sound is eartips dependent, stiff cable (though MK3 also available for purchase from MT without a cable).

The product was provided to me free of charge for the review purpose in exchange for my honest opinion.

Manufacturer/product website:  UM.  Available for sale from MusicTeck with a stock cable edition or without cable as well as with other cables at a discount.  Also, CIEM version available from a separate link.

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Intro.

Right before the CanJam NYC ’23, UM made the announcement about the upcoming version of their popular Mest Series iems, MK3 model.  Then, at the show many got a chance to audition the pre-production version dressed in a ceramic blue shell at Musicteck table, and even to try another special version with a switch to enable/disable BCD driver to hear the effect of it.  Not sure if that shell was just a design prototype or maybe UM reacted to visitor’s feedback, but when the official MK3 release rolled out, these shells looked completely different, very similar to limited-edition Indigo model.  And maybe for those who already got a blue Indigo version, UM decided to offer MK3 in two variants, including a red one.

Mest MK2 was UM’s very successful release for many reasons, a unique quadbrid design and tuning, collection of the included brand name accessories, and the kilobuck pricing without crossing the mega kilobuck threshold.  And the same happened after the release of Indigo, a limited-edition special version of retuned Mest that got a facelift borrowed from UM’s flagship models.  Some people even called Indigo’s tuning “MK3”, and I think UM took this feedback very seriously.  I only spent a brief time with Indigo and really enjoyed it, and when MK3 review sample arrived, I got flooded with questions of people mostly interested in comparison to MK2 and Indigo since other comparisons were already covered in MK2 review.

The reason why it took me a few extra weeks to finish this review, aside from a turmoil of personal family events, was because I have been trying to locate Indigo IEM loaner which turned out to be quite a challenge.  This Mest MK3 review will follow my usual format, but due to an overwhelming number of requests, aside from a detailed sound analysis, I will focus only on comparison of MK3 to MK2, Indigo, and… MM since to my surprise I also got quite a few questions to compare MK3 to UM’s current flagship Mentor Multiverse.  So, let’s proceed.

Unboxing and Accessories.

Unboxing experience of MK3 is a little different from MK2 and Indigo.  The 2-tier packaging box has been replaced with a top cover flip-open box with a deep foam insert where you will find a pair of MK3 shells along with a new PWA cable in either Cobalt Blue or Melon Red nylon sleeve matching the faceplate finish of IEMs.  There are also 2 sets (S/M/L each) of new UM Transparent umbrella shaped eartips made out of soft food-grade silicone material.  One set is called “open” with 6 symmetric holes at the top and the other set is non-perforated with petal-shaped edges.  These are the same eartips included with UM’s U-Free TWS earphones.

Also included were a warranty card, premium grey cleaning pad, double-pocket blue mesh bag which is useful to keep shells separated, emerald leather cable wrap, and a new matching emerald leather round case.  I was a bit surprised since previous Mest releases included Dignis rectangular zipper-top case.  I’m not sure if this round leather case is by Dignis or another manufacturer, and it does look nice, but it’s not as roomy as Dignis case.

Cable.

Continuing with PWA collaboration (Peter Wong Audio – PWA), these IEMs come stock with a new cable in either Cobalt Blue or Melon Red nylon sleeve flavor matching the faceplate finish of MK3 models.  The intimate details of PWA cable design are usually a mystery, though we do know this cable has 4 pure OCC copper ultra-low resistance conductors, 26AWG in thickness each, and a shielding layer.  The cable hardware is the same updated design you will find in all latest PWA cables, and depending on which color of IEMs you choose, the hardware will be matching in either blue or red.

The part of the cable above the splitter has a soft PVC non-microphonic coating and pre-shaped heatshrink earhooks.  The combined part of the cable below, between the splitter and headphone plug, has a nylon sleeve with a shielding encapsulating both of the cables.  As a result, this part of the cable is stiffer in comparison to a typically braided or twisted design.  That actually created a bit of a controversy with a number of people criticizing the ergonomics of the cable.  Musicteck noticed this feedback and responded with an offer of MK3 without a cable, or with an alternative option of a few other cables you can get at 50% discount with a purchase of cable-less MK3.

I will talk more about different cables I tried with MK3 in a dedicated section of my review, but personally I went back to using the stock cable.  Cable use is subjective and it is always good to have choices, plus, I respect when either manufacturer or retailer listens to customer feedback.

Design.

When Indigo IEMs were announced, their design was a step up from MK2 with an addition of 2 more EST drivers.  MK3 has the same driver config as Indigo, featuring 10 driver 5-way crossover quadbrid design with 10mm DD, 2BA mids, 2BA treble, 4EST ultra-high, and a new Silver-Palladium alloy piezoelectric Bone Conduction Driver (BCD).  This new BCD driver has 27 ceramic coatings, each 23-25um in thickness.  I will talk more about the effect of BCD driver in sound analysis section of the review based on my testing of their demo unit at CanJam which had a switch to enable/disable this driver.

As far as the shell goes, it is carbon fiber, thus Mest MKIII CF name, and comes in 2 color variants matching Cobalt Blue and Melon Red themes.  Also, similar to Indigo design, the faceplate features an alloy frame around an all-new Fruitwood material insert in blue and red.  There is also a small pinhole vent at the top, closer to the faceplate, 2pin socket is flush with the shell, and nozzle is metal with non-removable mesh cover at the tip.  The red version cost more money, and I think it’s due to a difference in the material cost/labor, though I’m not 100% sure about exact details.  The shells are beautiful, and I think those audiophiles who already got and keeping the Indigo will probably go for a complementary red color.  I was also told by Musicteck that despite higher price of the red faceplate, they often run special deals.

From a distance, MK3 blue looks nearly identical to Indigo, including the same shape and size of the shell.  The only noticeable difference is Indigo having a bronze alloy frame around faceplate, while MK3 has golden alloy and etched serial number on the right side and “Mest MKIII” on the left.  And, obviously, they have different cables.

The fit.

Page 2 – Sound Analysis, Eartips selection and Cable pair up.
Page 3 – Comparison, Source pair up, and Conclusion.