When you’re tired of the same old, same old; sometimes a switch is all you need. The Model X houses two changeable signatures so you’ll never be bored with the music.

Life is full of tough, petty, meandering choices, like chocolate/vanilla, money/fame, dieting/not dieting. Some you can go back and try the other, but others are substantial or large enough that you have to pick one and forever hold your peace, like a television, car or wife. At least until they give out lol.

In the IEM (in-ear monitor) world it’s just as tricky. You have a classic, followed by a variation of it, but with extra bass. History has given us VSonic GR07/Bass Edition, Hidition NT6/ProJH Audio 13/16, just to name a few. You tear your hair out poring through forums and reviews hoping to find a consensus (you won’t), since bass tastes, like fetishes, are extremely personal.

Like a little meme said, why not both? To have a regular signature, and also a bassier one when the mood (or curiosity) calls for it. Meaning you can have your cake and uh, have more cake. Lime Ears, a small company from distant Poland, practices this philosophy by incorporating a bass switch into some of their IEMs.

The switch was the main feature in their flagship, the Aether, and it has enjoyed great success because it’s basically buying two IEMs for the price of one. Today we look at Aether’s second-in-command, Model X. Mr. Spock to your Captain Kirk, if you will.

Black tie event, guys. Suit up everyone.

The Model X reviewed today is the universal version, housing 4 balanced armatures (BAs) in a 2 low, 1 mid and 1 high configuration. The X features Lime Ears’ in-house technologies:
  • PAR (Passive Acoustic Resonator)
  • VariBore
PAR is a sound bore tuned to even out the high frequencies; while VariBore uses sound tubes in optimized diameters for each frequency band.

And of course, the fabled switch. An easy flick up introduces an 8db boost to the lower-end frequencies from 800Hz down. Which means, for common folk like you and me, moar bass and a fuller, meatier sound. Hulk to your Bruce Banner. The Model X retails for €890.00 (~USD1000) and is available in universal or custom versions through their official website.

I’d like to thank Emil and Piotr from Lime Ears for their prompt communication and enthusiastic response in providing this loan unit. It’s been a pleasure talking to both of you.

This article was first published in Headphonesty.

Equipment Used


  • Sony NW-WM1A “K” Modded, FW 2.0
  • Lime Ears Model X
  • FiiO FA7
  • Jomo Audio Flamenco
Albums Listened
  • Bruno Mars – 24K Magic
  • Daft Punk – Random Access Memories
  • Ed Sheeran – Divide
  • Fleetwood Mac – Rumours
  • Jason Donovan – Greatest Hits
  • Macy Gray – Stripped
  • Prince – 1999
  • Taylor Swift – 1989
  • The Eagles – Hell Freezes Over

Packaging and Accessories

The Model X is packed with love. A prim, proper cardboard box greeted me, dressed in tuxedo black. The parcel felt unusually heavy, and now I know all the extra heft went to the aluminium case. You’ve heard of something built like a tank, well the case IS the tank. You can dent an actual tank with it, or knock a bird unconscious if you fling it in the air.

The case continues the tuxedo theme. Might be a coincidence that the Model X logo looks like a bow-tie when turned sideways, for unintentional class and charm! It’s roomy enough to hold the IEM, an extra cable, and all the ear tips for on-the-go. It’s heavy, but it will also outlive me.

The lunchbox of your dreams.

Completing the accessory set is the stock Plastics One cable, 9 pairs of ear tips, and a black cotton pouch. The branded ear tips are precisely what the world needs right now. A chocolate-box assortment of tips from Symbio (S, M, L), SpinFit (XS, S, M, L) and Comply (2 pairs M) mean the best in the market are provided, and you can definitely keep them for use with other IEMs.

I might have received special treatment because the cotton pouch is filled with traditional Polish cream fudge candy (krówki). You might or might not get them, but they’re sure delectable, and definitely contributed towards the final score of the review lol.

Design and Build Quality

The Model X marks the Lime Ears’ first foray into universal IEMs after making a career out of crafting only customs. It comes in an amorphous, take-it-or-leave-it shape bearing much resemblance to their custom brethren. A groove here, a bend there and a ridge in between, all in the name of comfort.

But in a stylistic statement of sorts, the X pairs dark smoke acrylic shells with black carbon fibre faceplates. The lime green logos break the monotony, imbuing a sense of playfulness, so things don’t get too formal or stiff upper-lippy. At the tip, sleek 2017A aluminium nozzles complete the look, with three bores of different diameters showcasing their VariBore technology.

There’s very little to fault with the design other than the overtly masculine appearance. I like to get in touch with my feminine side. As for build quality, they are as durable as your regular custom IEMs, meaning they’re plastic. Don’t step on ‘em, squish ‘em, or drop ‘em and you’ll be right as rain. Better yet put them in the aluminium case to survive World War III.

Extra marks for the delicious krówki, which translates to “little cows”.

Fit, Comfort and Isolation

When your bread and butter and bacon has been custom-fit IEMs, comfort and fit comes as second nature. I bet they could mold the Model X housing with their eyes closed. Sure enough, the X is a securely-fitting IEM, with comfort to spare for days and days. Have you ever looked everywhere for a sock only to realize you were wearing them all this time? Same feeling!

The amorphous shape might look like fascinating black jelly to you and me, but plays an integral part in the glove-like fit and supreme ease of wear. The switch, the only thing that doesn’t merge with the loving contours of the X, is located on the faceplate, and doesn’t touch any part of the ear anatomy.

Isolation is good, just about as good as a universal IEM allows. With SpinFit tips, I was able to keep the environment quiet enough for critical listening. In one instance, only after taking the Model X off did I realize there was construction work nearby. That’s commendable, unless the building is collapsing around you and you have no idea, then it’s bad.

Sound Quality

Think fast, what animal can change to adapt to new circumstances? If you answered chameleon you’d be correct, if you said “every living thing on earth” you’d also be correct. Not enough food? Eat less! Not enough sleep? Sleep more the next day! Too many children? Less sexy time!

While Model X hasn’t achieved “living thing” status yet, it comes with two sound signatures to adapt to listeners’ needs. The bass switch is there not just for the boom-boom. It can be activated to become more audible in low-volume listening, or turned on in a noisy environment for better immersion.

Overall Sound Signature

The Model X can be enjoyed two ways: dead neutral, or neutral-warm at the flick of a switch. The neutral sound is flat as an airport runway from bass to treble, but features incredible clarity and transparency like a dip in a chilly pool. It’s useful for studio monitoring, and some people do derive much enjoyment from a cold sound signature. Vengeful people maybe.

The other signature is friendlier to the ears and wickedly fun. With an elevated bass and lower mids region, instruments and male voices sound more full-bodied and correct in timbre. The mids and treble are unaffected from the base signature, so the note clarity and otherworldly detail are still mostly intact. It’s just a dip in a bubbly spa this time.

Listening Conditions

Critical listening was done after 50 hours of burn-in. BA-based IEMs normally don’t require burn-in, but I’m dense that way. A large chunk of the review was written while using Sony’s NW-WM1A Walkman modded by Project K, and the stock cable. The ear tips of choice were SpinFits, which convey the best seal, fit and comfort while not being detrimental to the sound.

Couldn’t find actual limes, so here’s something else that’s green.


Imagine yourself sliding into a skin-tight leather catsuit. Ok, you can’t, now imagine you’re Anne Hathaway. Easy does it. The leather adheres to the skin so securely nothing comes between them, like a vacuum. This is your Model X bass, skin-tight and airtight. The bass is as taut and disciplined as a supervillain or Batman’s on-again, off-again girlfriend.

The bass is, if you’ve been reading, lean and mean, with perhaps a too-quick decay. Extension is deep-reaching, but the sub-bass barely tickles your throat. You won’t feel the giddy heights of a pulsating sub-bass. The midbass conveys a tinge of warmth and body. Note hits are tidy, airy, and velvety-textured with great detail. In some passages, you wish there were more slam and impact though.

With the bass switch on, and it’s a brilliant change much closer to my preferences. Notes are made rounder, warmer and denser, sounding immediately more natural with a realistic timbre. However, there isn’t a satisfying, visceral sub-bass rumble, and the bass doesn’t move as much air as I like (my reference is a hair-dryer). Jokes aside, the switch is the game-changer for Model X and strews improvements across the signature.


Like traipsing in fields of daisies with no underwear on, the mids are airy, carefree and liberating. The attention-grabber of the outfit (or lack thereof), the mids are addictively crystal-clear and transparent. Notes possess just enough body to reflect a lifelike timbre, with a fun twist. Air follows each note like lovers’ gentle blows (don’t go there), lifting the signature skywards.

The layering is superb, perhaps elite-class. Even in busy tracks, you won’t lose track of what’s going on. You can pick out any instrument and just follow it like the stalker you are. Attack and decay are well-controlled as well. Notes flit in and out of the soundscape with speed and precision, aided by a bountifully black background.

The upper mids are acutely raised for all the airy, textury action to happen. So lady vocals and brass instruments are lively, articulate, and clear as a window, giving you an up-close, nothing-to-hide presentation that captures nuances like second nature.

The lower mids are flat and lackadaisical in neutral mode, but with the bass switch on, mamma mia! Male vocals, strings and guitars receive a welcome, robust boost of body, like a silicon injection in er, strategic spots, for rounder, firmer and dare I say more voluptuous notes. Seriously the bass switch is a godsend.

He hopes to land a role in a crime drama and finally be taken seriously.


Moving up from the clean and clear mids, the treble doesn’t deviate much from the baseline, if at all. Like a high heat sear, Model X’s treble aims for maximum impact in the shortest time possible, bringing the sizzle to an already vibrant signature.

Notes have a crispy edginess to them, especially at the lower treble region, veering towards brightness and stopping short of sibilance most times. Cymbals and hi-hats have a crunchy texture followed by a swift decay. Alas, sometimes the treble is overdone, leaving a burnt, charred aftertaste to an otherwise glorious meal. Too much bite and bark.

But 90% of the time, the treble is a people pleaser. The addictive skyward airiness, the lightning-fast transients, and the risk-taking, Evel Knievel extension that is brilliant yet dangerous, dares us to risk our ears and sanity to take in that massively detailed, ear-tickling treble that has as much sparkle as fireworks on the 4th of July.

Soundstage and Imaging

We like to trap stuff to admire in our own time. That’s why we put high-flying birds in cages, kidnap pandas so they’ll copulate to procreate, and uh, capture photos of food. The Model X’s light and airy presentation resemble a firefly that you’d like to hold in a glass jar so it only shines for you, you voyeuristic devil.

To keep the firefly happy, the glass jar is adequately spacious, but only just. The Model X has a tight, disciplined sound matched only by a tight, disciplined soundstage. It borders on the intimate, with equal height, depth, and width for an encompassing sound that never floats away, but serves the signature.

The imaging and separation though, is surely one of the best the market has to offer. With steely precision, layers are um, well-layered and intricate. Spatial cues are well-defined, you’ll have no trouble guessing what comes from where. This is all thanks to the brighter-edged, nimble notes working its mojo with plenty of black space to spare in the background. Ever wanted to dissect a song surgically? Now you can.

Dangle ‘em, tangle ‘em and mangle ‘em.


FiiO FA7

I didn’t mean to start this section with a pummelling, but unfortunately FiiO’s value-oriented FA7 is the only other 4BA IEM in my possession at this time. Again, at USD300 the FA7 isn’t exactly cheap, but when Model X is aiming for the heels of higher-priced flagships, you know FA7 has its work cut out to itty bitty pieces.

Let’s start with the positives. The FA7 showcases the continuing evolution of FiiO has a brand to be reckoned with, and is probably their most mature tuning to date. There’s plenty to like about the FA7, the robust build, head-turning faceplates, great fit and the accessible, warm sound signature.

It’s just that, when put against Lime Ears who’ve spent quite some time in the TOTL (top-of-the-line) arena, the differences are really telling. Model X obliterates FA7 in technical ability, boasting lengthier extension across both ends; cleaner, tighter notes with better definition and texture; a darker, airier background; and laser-guided imaging precision.

These blingy faceplates are built to hypnotise.

With that technical backing, Model X flexes its might in all departments. The bass hits deeper and more viscerally, and decays faster than FA7, sounding more engrossing and fun. Mids are more resolved and articulate, with crunchier texture and bite. The treble showcases much better micro-detail retrieval, and carries gobs of air wherever it goes.

FA7 is, by all means, a more forgiving, less fatiguing listen, and would be more of interest to those looking for a smooth, inoffensive sound. But overall, the Model X is a technical masterclass, with top marks in speed, precision, and fun. The FA7 is humbled, and made to sound blunt, slow and plodding while lacking air and crispness.

Jomo Audio Flamenco

Word association: when someone mentions “neutral monitor”, 9 times out of 10 I think of Jomo Audio’s Flamenco, their old flagship (not the Latin dance). It features 11 BAs with a killer neutral tuning, killer switches for bass and treble, and a murderous price (starts at a whopping SGD2999 or ~USD2200 depending on options).

While this might seem like a matchup between David and some giant, Model X and Flamenco are more spirit brothers, both carrying a neutral signature with switches to augment the sound. Flamenco has two fun buttons as opposed to Model X’s single switch, but for the sake of fairness, let’s just twiddle the bass switches.

Straight up, I was amazed at how remarkably similar they both sounded. They possess blazing-fast note speed, an eye for details, top tier transparency, a compact stage size and disciplined, razor-clean imaging. Like brothers from a different mother. The presentation too is similar, opting for precise, well-measured notes, immense air, and a bright tilt for excitement.

Before you can yell “doppelganger”, there are slight differences upon closer scrutiny. Flamenco sounds more organic, true-to-life, and effortless. There is an ease in which the notes flow into each other, and it scores massive points in musicality. This is achieved while not surrendering any of the resolution, speed and transparency that it is known for. It’s a proper top-tier monitor.

Model X however, sounds brighter, harsher and grainier than Flamenco. There is, unfortunately, a faint digital, metallic edginess to the notes, more noticeable in the treble. For mids, X leans towards articulation, while Flamenco has more accurate timbre. X’s bass is slightly boomier and more authoritative than Flamenco’s, lending a more V-shaped signature overall.

So Model X comes across as the excitable loose cannon, while Flamenco is more cultured, relaxed and provides minute refinement throughout. Next to the galvanic magnificence of Flamenco, Model X puts up more than a good fight. It’s flat-out amazing how well Model X keeps up despite the price difference. Baby Flamenco? Why yes!

If only it was a working timepiece.

Final Words

We like to look for the one IEM that can do it all. But no matter what we choose, concessions are made. Too much clarity sacrifices naturalness, too much note body foregoes airiness and congests the stage, too much smoothness puts you to sleep, too large a soundstage diffuses the sound and lacks engagement, et cetera et cetera.

Finding the perfect IEM is more of keeping what you want while accepting as little shortcomings as possible. It’s a balancing act, like walking a tightrope to profound madness. Lime Ears doesn’t have the solution, or “the one”, but proposes a workaround that allows you to have the best of two worlds, a reference and a fun signature, covering a great many genres in one swoop.

As some might say, X marks the spot. Or is it X barks the lot. Or maybe X sparks the thought. Enough. Model X is quite possibly the most versatile and accomplished IEM I know of in its price range, and provides much ammunition for the “you don’t need many drivers for great sound” argument. What’s more, Model X dares to dream, with technical abilities that rock the boat of pricier flagships.

History remembers the best duos in memory, like Lennon/McCartney, John/Taupin, Milli/Vanilli, bacon/eggs… anything but those Wham! guys. In the same rich vein, Model X’s dual signatures are different and dazzling enough to stand on their own, a dastardly duo that does it all to discerning and distinguished devotees. It’s an absolute joy to listen to.

- Versatile, well-implemented sound signatures
- Flagship-tier sound quality
- Elite imaging and layering
- Very good accessory set, especially the ear tips
- Excellent fit and comfort
- Good isolation
- Reasonably priced

- Generic design
- Heavy carry case
- Neutral tuning might be too sterile
- Treble is sometimes harsh
- Small soundstage

Rating: 4.5/5

Disclaimer:   I was sent the IKKO OH1 as a review sample by Patrick Lin after having a conversation about IKKO products on facebook.   If you have an interest in IKKO products, please visit their website, or facebook.  IKKO products can be purchased from Amazon here or purchased from Penon Audio here.  

Unboxing / Packaging:
The box has a white slip-cover with the ikko logo and earpiece adorning the front and specs on the rear.  inside is a black pressboard lift-top box again sporting the Ikko Logo.  Immediately under the lid, we find an envelope that contains the warranty card and instructions.  Beneath that, the earpieces are revealed in a foam tray at the upper end and the two sets of tips also housed in foam in the lower portion.  Beneath the tips hides the soft case with the cable inside it.

The kit included with the OH1 is fairly thorough, with 6 sets of tips (3 each vocal and balanced in SML), a soft carry case, the instructions and warranty card, and the cable.  Overall, for an IEM at this price level, the kit is equal to or better most brands and falls behind only ibasso (hard case) and Fiio (kitchen sink in kit).   I would have liked to see the pouch offer a pocket to keep the two earpieces from touching when in transit to prevent scratches.

Shells are cast aluminum anodized uniformly in a deep royal blue in a teardrop style.  Size is medium-large but depth of the shell is thinner than most which helps with getting good insertion and seal from a relatively short nozzle.  Unlike most models at this price point, nozzles are part of the inner shell and not a separate piece. I commend Ikko on doing this the harder way as that means more internal and external polishing of some pretty tight spaces to get the anodizing right and the sound channel correct.  Nozzles are at the lead edge of the shell with a forward and upward rake and have a pronouned lip.  Venting is a single port behind the nozzles on the interior of the shell and one on the upper surface of the shell between the two pin connector and the L/R designation.  Both earpieces have the Ikko logo and name along the rear of the shell and are very tastefully done.

Bass details are handled by a 10mm titanium plated dynamic driver while higher frequencies are handled by the Knowles 33518 balanced armature driver.  The 33518 is a newer Knowles driver that is targeted at hearing aids and audio above 1kHz per Knowles.   Some will recognize this pairing as being similar to the Fiio FH1 that also uses a 10 mm dynamic coupled to the 33518.  The Magaosi also uses the 33518 in a more limited role as the mid driver between 22955 (CI) Bass armature and the 29689 (ED) treble armature.   Nominal impedance is listed as 18Ω with a sensitivity of 106dB/mW which makes the OH1 easy to drive using low powered sources like phones and tablets.  I did find the OH1 scales well but was more than adequate when used directly from an android phone or iPad.

The cable is well done with all metal accents anodized to match the color of the earpieces and color matching is spot on.   the Jack is a 90º style that I prefer with a metal barrel and a black plastic strain relief above it.  The cabling itself is a 4 strand silver plated 5n oxygen free copper in a double helix (two wires twisted, then pairs twisted) from jack to splitter.  The splitter is also a blue metal barrel with each pair of the helix exiting to the earpieces.   Terminations have a pre-formed earhook without memory wire and end with metal cased .78 mm bi-pin connectors.  Right is duly marked with a red ring.  If there is a complaint here, the bi-pin connector on the iem is raised and the connector on the cable does not have a matching recess which makes the connection look a bit different than most other models.   Overall, a well done cable with nice accents to match the earpieces.   Now about that matching chin slider?  (wish it had one).

Two sets of tips are provided, one marked vocal and the other marked balanced.  Perhaps oddly, I found the vocal tips to be a bit more balanced and used those for the bulk of my listening notes.


Bass is the star of the show on the OH1 to me.  The OH1 has better than average extension at the low end and sub-bass is not only good in quantity, it is also good in quality.  Not boomy or loose, but tight, clean, and with better detail than expected.  Attack and decay are both better than expected with decay being only slightly slower than attack and still faster than expected for a dynamic driver.  In that respect the OH1 combines the best features of dynamic driver bass with the control of BA bass.  Sub-bass is foward of mid-bass (a preference for me) but detail and character remain consistent as you climb through the range.  Mid-bass shows no bleed into the mids and no bloom at all making this one of the cleanest two driver hybrids I have heard as the point between mid-bass and mids is usually where the hand-off between dynamic and BA takes place and more often than not the point at which coherency falls apart or a perceptible bass bleed is present.

As we move from the bass into the mid-range, the transition is fluid with no major drop-off or large spikes.  Mids are slightly behind the bass but not enough to even call it a recess.  Tonality is quite good which proves that Ikko has done more to tune the BA driver than the previously mentioned FH1.    Vocals show good clarity for both lower registers and upper with a mild push forward of upper-mids that gives female vocals just a touch more presence than lower voiced counterparts.   Details are quite good and timbre on vocals is as well.  Timbre on upper strings is a bit on the hot side and can come across as slightly brassy at times.   Guitar is particularly well rendered with both acoustic and electric sounding lifelike and energetic.

As we climb from the upper-mids into lower treble, we almost immediately plateau and stay put at the same level for most of the treble range.  This is in stark contrast to many iems that are a ball of spikes when looking at frequencies above 2kHz.  The OH1 does a good job with giving snare enough edge to be credible but not sounding sharp or harsh.   Overall, the treble feels quite laid-back and easy to listen to for extended sessions.  Clarity is good with a solid level of detail in the lower treble and then as it climbs into the higher ranges, detail and output begin to taper off pretty steeply above about 10kHz.   This makes for some air and sparkle while remaining non-fatiguing and polite.  The only drawback is as tracks get more complex with lots of treble-heavy parts, the OH1 can get a bit overwhelmed and sounds a bit thick.   This isnt a common issue, but something to know is a possibility so if you listen to a lot of treble-intensive works, you may wish to audition before purchase.

Soundstage / Imaging:
Soundstage has good depth (better than expected) and width (as expected) with the balance being slightly in favor of width.   While not as 3d as some, there is some sense of height and instrument positioning benefits.   I didn’t find any congestion to the stage and with width favored no tendency to place instruments behind each other instead of next to each other.  Binaural recordings like the Cowboy Junkies trinity session that I enjoy do a good job of showing off the stage and imaging capabilities of the OH1.   Overall imaging is class leading and competes well with models significantly above its price point.   Spatial cues are well rendered which makes the OH1  good for movie watching and maybe gaming although I am not a big gamer so cant speak directly to that point.  Layering is also quite good and I didn’t find that it bogged down or thickened as tracks got busier and more complex.


Fiio FH1
With both sharing a 10mm dynamic and the same BA driver this is a natural comparison.  With a $75 price difference maybe a bit less so, but lets do it all the same.    Both share a similar bass forward tuning with good slam but the OH1 notches the win for better control and depth.  Both are good, but OH1 is better.  Mids are very similar and again, this is more a matter of degree than difference with a slight edge going to the OH1 for better transition from bass to mids and a bit more energy in the upper mid-range.  Treble is again about equal, but here I had trouble picking a clear winner as the two are more similar than not.

Build-wise the OH-1 is the more polished product and both have solid cables.  The kit on the FH1 is better due to the addition of the pelican case and 2nd cable for use with a phone.

NiceHCK M6 (DMG Vented filter)
The M6 is a bit brighter and has a sharper edge to its sound than the more relaxed OH1.   This makes the OH1 sound more natural while the M6 at times sounds a bit strained and/or clinical and dry.  Mids are more forward on the M6 which again is mixed.  On some tracks the forward mids helps the M6 feel more engaging with strings in particular, but on others that forward push can result in a more strident tone and some sibilance at times.

Build-wise, both are quite good but quality of anodizing and cable go to the OH1 as the clear winner.

Magaosi X3
Again, I referenced the X3 earlier as sharing the mid-range driver with the OH1 so this is a natural comparison.  Bass slam goes to the OH1 without doubt as does low end extension.  Both models exhibit very good control of the bass so on that count we will call it a draw.   Mids are good on both and very similar but for me strings are a bit better on the X3 where the timbre is a bit more natural.  Highs are similar on both as neither has fantastic top end extension but the OH1 sounds less rolled off where the X3 has a lack of air at the high end.

Build-wise, this is quite a clash, the clear acrylic of the X3 with its sound tubes has a lot of appeal, but so does the polish of the OH1.  The kit is better on the X3 with its included hard case and bluetooth cable, but at $45 more, those items could be purchased separately for the OH1.

Moondrop Kanas Pro
The Kanas pro is way closer to neutral than the OH1 which has a much more V shaped (nearly U shaped at times) signature.  Bass is far more the star of the show with the OH1 than with the KP while mids are fuller on the KP, Treble is a bit more forward on the OH1 which gives the OH1 a bit more air and sparkle than the KP.  The KP has a bit more detail especially in the mids and lower treble.  Both share a sort of laid-back effortless delivery, but for me the KP is slightly better at it.

Build-wise both are stellar and both cables are equally good.  The OH1 does have the advantage of weighing about 1/2 what the KP does so may be more comfortable for long wear.

Thoughts / Conclusion:
First off, my thanks to Patrick and Ikko for sending me the OH1 to try.   I found the OH1 to be a great way to launch a new company into the busy audio landscape and it shows a level of capability well beyond what one would expect from an introductory model.  From the polished shell to the mature tuning, the OH1 has all the hallmarks of a seasoned product and competes well at its price point.   For those who like sub-bass rumble and a polite treble, the OH1 should be on your list to audition.    I’ve been using mine for a solid week as I write this review, and think they will likely retain a spot in my work lineup now that I am done writing.  For those times when you just want to relax and listen, they make a great companion.
  • Packaging - 7/10
  • Accessories - 6.5/10
  • Build Quality - 8/10
  • Bass - 8/10
  • Mids - 6.5/10
  • Treble - 6.5/10
  • Soundstage - 7/10
  • Imaging - 7/10
Pros:  build quality,  bass performance, solid mids w/ good detail, great clarity and separation, very open

Cons: carrying case doesn’t keep earpieces separated, can be harsh in upper mids, U shape is definitely not a reference tuning.

Simgot EM2 Review

by wilen/Audiofool

disclaimer:  Simgot kindly  sent the EM2 and MTW5 for review.   I have no financial interest in Simgot, nor are my words here influenced by any outside concern.    If you are interested in Simgot products, please check here for more details or visit their amazon store to purchase.

Unboxing / Packaging:
Packaging on the Simgot EM2 is classy and understated.  An outer slip-cover has a large stylized drawing of the EM Series earphones on the front.  Specs (in English) are on a sticker that is affixed to the shrink-wrap on the reverse and covers the original specs (in Chinese) beneath.  Also on the reverse is an exploded diagram of the EM2 done in a tastefully subdued gray on black background.   Once the slip-cover is removed, a black pressboard box is exposed with the Simgot Emblem on front again in subdued gloss black on flat black.  Lifting the cover off the box reveals a foam tray with earpieces at top and a leather carrying case below.  The cable and warranty cards are hidden beneath the foam tray while two cards of tips are tucked neatly into the carrying case.   Overall the packaging seems fitting for the price point represented and done very tastefully.

The EM2 comes with a well made leather case with Simgot logo on the front, slogan on the rear, and magnetic closure.   Inside the case are two cards that each contain a set of silicone eartips in three sizes.  Card 1 contains the standard tips while card 2 has bass enhancing tips.   The Cable has a velcro retainer but lacks a shirt clip.  If there is a ding, it is that the case is not large enough to store both the tip cards and the earphone but for most they will pick a tip from the cards and use it so carrying both cards of tips around is probably not all that likely anyway.
The two sets of tips do indeed make a difference in sound.  Both are made of the same material and seat to roughly the same depth, but the bore diameter is enough different to change the sonics.  I found Tip 1 to be more accurate and provide a closer to neutral signature while Tip 2 was more relaxed and more musical for long listening sessions.   Tip 1 is brighter and can verge on too bright at times while tip 2 emphasizes the lower end more and helps offset the natural tendency of the EM2 to be a bit bright.

Shells are transparent plastic with a mild smoking as I received what Simgot lists as the black model.   This is a nice change of pace as all the color options are subdued.    A single vent is on the underside of the shell immediately behind the nozzle.   The Left earpiece is labeled "BA x1 Dynamic x1" while the right earpiece is labeled "2 way hybrid iem".    Nozzles exit the lead edge of the iem with a slightly forward rake.  Tips seat deeply on the nozzles which does limit insertion depth and a large ring on the nozzle prevents slippage of the tips.    The earpieces themselves are mid-sized and I think only the smallest of ears might find them problematic.  Comfort is good as they sit firmly in place without any high spots or odd angles and the ear-hooks work well to prevent movement during activity.   I also found the EM2 to be lighter than many earpieces which contributes to overall comfort as well.

The EM2 is a hybrid using the same titanium coated 10mm dynamic driver of EN700 fame paired with the Knowles 32873 balanced armature to handle top end duties.    Nominal impedance is listed as 10Ω which may be low enough to cause some issues with impedance matching.   Sensitivity is listed as 100dB/mw (at 1kHz) suggesting that the EM2 should be easy to drive using a smartphone or tablet.   I found it performed well from Android (Moto) and Apple (10r) phones but does benefit from having a bit more power available to it.  It scales well to a point but beyond that I saw no additional gains.  (My Opus #1s on mid gain showed the same characteristics as going to the Burson Fun with its significantly higher horsepower).

I was particularly impressed with the .78mm bi-pin housing on the Simgot cable.  The connectors are recessed inside the housing to protect the pins and to strengthen the connection when installed.  This is an excellent idea, but does limit use of 3rd party cables as they tend to look a bit disjointed in comparison.     The cable itself is a 4 core copper braid up to the splitter and two twisted pairs above.   The jack and splitter both feature a rose gold colored metal housing encased in a clear rubber like plastic.  The Chin slider is the same metal but lacks the coating.   The Jack is a straight 3.5mm TRS design with good strain relief so should last well unless abused.  the bi-pin connectors also share the same rose gold metal ring giving the cable a very nice overall look.  Two minor issues do warrant mentioning. First, the Chin slider is mostly ornamental as it is too loose on the cable and simply falls back to rest on top of the splitter during use.  Second, the L/R markings on the connectors are clear on clear and can be very difficult to make out.  A colored dot would go a long way to making this easier to see.


Sub-bass is present but in limited quantity and is enhanced some by using the bass tips provided.  I found the bass on the EM2 to be very tip sensitive so tip rolling to find the best combination for the individual will likely be needed.   I Found the provided bass tips worked well, but Spiral dots and the Auvio Wide bore worked even better for me.   With the larger bore tips, sub-bass is still recessed but slightly less so and the EM2 manages to have some low rumble.  Mid-bass is a bit more forward but equally well controlled.   Attack is slightly faster than decay leaving a bit of warmth lingering but decay is not so slow as to feel overly thick or heavy.  Even with bass tips, this IEM leans toward the neutral or mild w shape and will not please a basshead.

I'm well pleased with the mids on the EM2 as they are much more the star of the show than on most other brands at this same price point.  Lower mids  transition from the mid-bass smoothly and have good weight to them giving lower register vocals good body and timbre.   True mids are slightly behind the lower mids but still not pronouncedly so.   The upper mids rise above the rest of the signature (along with lower treble) but only mildly so and give female vocals and higher strings a bit of extra life.  Higher pitched vocals are slightly more forward and intimate than their lower voiced counterparts as a result, but not so much so as to feel incoherent in the overall.

This is what I was most interested in hearing.  Having had a couple of earlier Simgot models, I know treble has been a struggle for them at times.  (I was unabashedly not a fan of the EN700 pro for exactly this reason).   Well, I can say that crossing the dynamic a bit lower and adding the 32873 Knowles BA has definitely improved the treble on the EM2 compared to earlier efforts.  This is movement in the right direction.    The lower treble flows from the upper mids without a big forward jump and gives snare a nice clean edge that was not present in earlier versions.  Roll-off is fairly steep above 10kHz which removes any tendency toward stridency and I found I could wear the EM2 for extended periods without notable fatigue.   Air and sparkle could be slightly better, but this is an obvious trade off to achieve the polite treble of the EM2.

Soundstage / Imaging:  
Soundstage is wider than deep and makes the listener feel as if they are slightly back from the stage in a small auditorium.  I did not find any tendency to get congested as tracks got more complex and instrument separation is very good throughout the entire range.  Imaging is good and instrument position on the stage is easily discernible as well as movements around the stage.   I did not find them to have a holographic stage as most detail seems to come from more or less directly in front of the listener rather than feeling like you were at the center of the production.

Ibasso IT01
The IT01 is more V shaped than the EM2 and has more bass slam but mids are recessed compared to the EM2 and lack some detail.   The EM2 comes much closer to neutral and treble has a more natural timbre than the IT01.     Those looking for a fuller, more bass heavy sound will prefer the IT01 while those looking for more detail in a thinner more neutral profile will prefer the EM2 (even with the bass tips).

Fiio F9 Pro
The F9 Pro is much more V shaped than the EM2 and delivers more bass and especially sub-bass.  Those wanting bass slam will appreciate the F9 while those looking for a more neutral and natural presentation will prefer the EM2.  Treble is more polite on the EM2 than on the F9 Pro and while the pro improved on the overly sharp treble of the original F9, it still has more of a tendency to become strident than the EM2.

NiceHCK M6
The M6 is much more V shaped and even with the filters is more bass heavy than the EM2.  Both have really good mids, but the M6 requires the use of the DMG vented filter to really bring them out.   The M6 wins on tuning options, while the EM2 has a more natural sound out of the box without having to add additional filters.    Those who enjoy modding will prefer the M6 with the greater flexibility, while those who wish to just use their eims without having to fiddle with it, the EM2 provides a solid option.

Thoughts / Conclusion:
Simgot has departed from the norm with the EM2.  While most of the Chi-fi world has gone to packing in as many drivers as possible and tunes for the big V with lots of extra treble energy, the EM2 eschews this for a much simpler and more coherent approach.   The upside is a much more fluid presentation without the choppiness and grain often associated with the multi-BA budget iems.    The detail is better in both quantity and quality than expected and no single range jumps out at the user.    Those tired of the over-emphasized bass and treble at the expense of mids will really enjoy the EM2 as will those looking for snare and cymbals to be crisp without being metallic as is so often the case.     Overall, I find the EM2 represents good value as it offers a very different signature than typical at the price point combined with solid construction and a well thought out kit.