Letshuoer S12 Pro Review

Letshuoer S12 Pro ($169)

It has been awhile since I first received the Letshuoer S12 Pro and so I realize how late to the party I am. However during that time the S12 Pro has been a constant iem that I’ve reached for in leisurely listening. I purchased the S12 Pro off of Amazon US on sale for $149 about a month and a half ago and really have been meaning to complete a proper review. Unfortunately priorities, life, and an all consuming and ever growing l ultra-budget chifi market has kept me from reviewing this beauty of a set. 

The S12 Lineup

The S12 Pro also carries the moniker “6th anniversary edition”, and for those who somehow don’t know, it is a Planar driven iem which followed the original *S12* as well as the ‘Zeos tuned’ Z12. All of which have the same build, same shell. However from what I have gathered, some of the  internals have been upgraded (more on that later). There has also been some minimal tweaks to the tuning and some paint and accessory changes.

I won’t go into all the Planar iems which caused this deluge of “Planar Madness” to strike the audio community, there are plenty of reviews and write-ups which outline how we got here. What I will do is simply complete a review of an iem which I have grown quite fond of and will likely add a comparison or two. I really have enjoyed my time with this set and I’d like to tell you why. 

*Mahir Efe Falay’s Letshuoer S12 (original S12) review*

S12P Pros

-Wonderful build 

-Striking appearance 

-The included modular cable is awesome

-One of the better tuned planar driver iems

-Tight and authoritative low end

-Transients 

-Resolution 

-Separation and layering

-All together smooth and non-fatiguing 

-Great modular cable

S12P Cons

-Could use a touch more air up top for some, also, 

-May be a bit too HOT at times for some people

-Very slight Planar timbre (not really a con) (rare occurrence) 

-Soundstage isn’t enormous (not really a con either) 

Packaging

I love unboxing, it is a short-lived hit of dopamine that is so satisfying… and then it’s gone. I love busting out my blade that I have always attached to my hip, love to feel the snap of the quick release and the PANG of the steel snapping open… just to cut some… cellophane? HA! It’s the little things in life ladies and gents. The quick slice of the protective sticker and I’m in business. Anyways, I really enjoyed the unboxing on the S12P because I had an idea what was included. By this point I’d already seen some unboxing so, I suppose it wasn’t much of a mystery. 

What’s inside

The S12P come in a rectangular box within a sleeve. As you open the box you are greeted with the beautiful earphones staring back at you. To speed this up… within the box you find the amazing cable and extra plugs (more in that later). Also, you’ll find three pairs of a lighter color eartip, three pairs of a darker gray eartip and three pairs of foam eartips which come in a handy little case. Of course, you’ll find the paperwork and Letshuoer also threw in a cleaning brush tool. The last accessory is the black faux leather carrying case with a nice zipper and of decent enough size. As a whole this is about what you should expect with an unboxing. 

Design/Build/Isolation & Fit/Durability/Other features 

Design

The S12P are downright striking in appearance. A very simple yet also beautifully designed earphone all the way around. Colored in a matte finish is this navy blue colorway with hints of purple hues which appears bold, distinguished and regal. Accenting the gorgeous paint job is a protruding small rectangle housing where the female 2-pin connector is located with a beveled strip of shiny silver outlining it, which adds such a distinct contrast to the confident looking shells. I have the hardest time deciding if there is bluer than purple, or more purple than blue? 

I love the design of this set. I’d be lying if I said I didn’t twist them around in my hands looking at them from different angles. The Matte finish is the perfect finish, and the choice of aluminum is as much sturdy as it is light. Whoever took part in the design should get a raise… Letshuoer let’s make that happen. 

Build

The S12P is constructed completely out of CNC machined Aluminum from the back of the shells all the way to the nozzle. The Shells are very smooth with a purposeful curvature and without a jagged edge on them. You’ll find one fairly large front vent and another rear vent hidden next to the female 2-pin connector. The nozzle doesn’t reach too shallow nor too deep but sits somewhere in the middle for me. Sitting on the nozzle is a quality metal mesh grill with a cool looking design pattern. Really, this set is quality from back to front. 

Internals

The S12P uses a custom 14.8 mm Planar diaphragm which I believe is the same diaphragm as its predecessors. The chassis housing the driver is said to have independent front & rear acoustic chambers, as well as multiple vents to alleviate pressure build up and from what I read in their advertising, these help for a more consistent channel matching. 

Isolation & Fit

The S12P isolates about as well as any iem on the market. Nothing to write home about, let’s just put it that way. Honestly when music is playing you can’t hear anything but the music. I suppose these would be fine for out and about listening but don’t think they isolate the outside world like a proper ANC set. For myself I get a great seal and isolation is above average. 

As far as fit is concerned… ugh. I will complain about this until I simply stop adding the most subjective topic of fitment. For me these fit perfectly. The slightly angled nozzle helps these earphones to sit perfectly nestled in my ear, almost like they grew there. For you however, I have zero clue how they will work. 

Cable

One of my favorite aspects of the S12P is the pliable, durable feeling and flat-out sweet looking cable. I love the nice and thick look of this perfect addition to the S12P. Made of 4 cores of Silver-plated Monocrystalline Copper with a very user friendly rubber type coating which protects & insulates the wire. Yes this set and cable are dope looking but the best part that Letshuoer addressed is the fact that a swappable modular connection was added. 

Letshuoer gives the choice to use a 3.5mm single ended jack or go with a balanced 2.5mm or 4.4mm jack depending on the source you have. For me personally I went entirely with the 4.4 jack from beginning to end of this review. Minus of course, when I used a couple lower powered sources for a brief time and switched to the single ended plug. I love a good cable and even more I love an aesthetically pleasing, eye-catching cable that feels as premium as the earphones in my ear. I love the contrast of color between the cable and the plugs, y-split and 2 pin housing. The cable is a twisting mix of white and almost light brown while the hardware on the cable is the same navy blue and purple mix (pictured). To me this cable is very well designed. 

Drivability 

The Letshuoer S12 Pro is said to have an impedance of 16 ohms and a sensitivity of 102 dB. Letshuoer made sure that the S12P were not impossible to drive well with most any source but in truth this set loves some good clean power. I’m not talking about a desktop setup outputting a million watts, but I am talking about a good and strong dongle dac at the least. Let’s put it this way, for the greatest majority of this review I used the Shanling M6 Ultra or the Ibasso Dx240, both on high gain and both checking in at around 30-40/100 on the volume scale. She was sangin’ people!

Will my dongle be enough

Of course not everyone has a $1000 or more Dap sitting around. In fact, I’d venture to say that most people in the community have at best a decent dongle dac and saved up to purchase the S12P or are at least thinking about purchasing this set and want to know… “Will my dongle be enough to drive the S12 Pro or do I need more?”. The answer, assuming most people have at the very least a decently powered dongle dac, is yes.

For instance, I used my Shanling UA2 on 2.5 balanced and it powered the S12P perfectly fine. In fact, it was more than enough. The IFi Go Blu (4.4) absolutely rocked this set and really synergized with the tuning of the S12P. Both the Ua2 and the Go Blu output around 190-240 mw per 32 ohms respectively and replayed this set with a ton of headroom and dynamism. 

More Power

Still, to get the absolute best of this planar driven earphone I do think it sounds the best, the most open, the most dynamic and at home, when using something with more power. Needless to say, that both of my daps (M6 Ultra & Dx240) equally made the most of the S12P. Both adding their own flavor to the sound. The Quad AK4493SEQ chips in the M6 Ultra and the ES9038 Pro chip within the DX240 both have fantastic synergism and show the adaptability of the S12 Pro. I suppose the same result would be had with both the original S12 as well as the Zeos tuned Z12. 

Quick Sound Impressions 

I would definitely call the S12P a mild V-shaped iem with a smoother replay. Unfortunately, I have not heard the original S12, but from what I’ve put together (from older S12 reviews as well as a graph comparison) there is a minor reduction in the upper-mids and treble as well as a bump or two more in the bass region. I hear a mildly warm and all together smooth sound with good representation of all areas of the mix. 

The bass hits with more than adequate authority and a planar like quickness. The midrange sits back only a hair but still has enough good energy for solid vocal replay. The treble is airy enough and detailed with good presence and extension while never really creating any fatigue. The playback as a whole is detailed and fast with a quicker transient response and good atmosphere. I would certainly call the S12P a fun and very dynamic listen that can play with multiple genres and satisfy many listening styles. Really this is an energetic display of a safe tuning and for me… it works. 

Bass

“In My Feelings” by Drake is a banger of a song with a deep bassline which drops within moments of the song’s beginning. The S12P sound almost DD-like in the way they boom with an atmospheric and sonorously penetrating replay of this song. I don’t know how good of a song choice that is though, honestly any iem pounds to that track. So, I switched over to “Country Child” by Robert Finley as the deep bass guitar groove in tandem with the kick drum. Both come across snappy but with separation and enough layering and texture to show depth and never does the bass overshadow too much of the rest of the spectrum. The sub-bass checks out folks as I can feel the bass as much as hear it. Only when called upon. 

Nicely Rendered Slam

The mid-bass has a nicely rendered slam with a nimble attack and decay. I hear just enough linger to create an atmospheric character. Like I said, this set is missing nothing next to a dynamic driver. Maybe a DD has slightly more visceral and intensive rumble, but at that point it may be more of a problem against the rest of the mix. 

Considering this is a planar iem, I think the S12P does bass very well. “Billie Jean” by Weezer hits right out the gate with a hard kick drum followed by a snare which is quickly followed by a rolling bassline. As far as I’m concerned the S12P absolutely kills it with this track. Everything is so snappy in its attack with hard and rounded edges and precise with transients. The mid bass doesn’t show any signs of hollowness or fuzziness but instead hits with the authority that any track would demand and comes across slightly colored and impactful. 

Never Muddy

There certainly is an emphasis in this region but that rise doesn’t ever come close to muddy or cross the midrange line adversely. I really enjoy the output here. I grew up on bass and I always need at least a generous portion so long as there is some semblance of control. The S12P is all control, all the time, without being overbearing or exhausting after long stretches of listening. Resolution and clarity are very nice in this region with a tidy and clean response. Well done, Letshuoer!

Midrange

Low-Mids

The midrange is well resolving, it carries a detailed sound with enough good energy to even add an emotional flair to my music. There is a subtle warmth in the low-mids which carries over to men’s voices as well as instruments in this region. Vocals have a transparent and somewhat natural sound that can be nicely crisp and technically adept to not miss subtleties. Take the song “Better Together” by Luke Combs. Luke always sounds forward in this song and every vocalized word is pushed by a breath of air which can be easily discerned and heard. I hear some depth to vocals and instruments with nice separation. Another plus is the energy and heft to men’s voices. Not too weighty or veiled and not too thin or dry. I should add that male voices do have a bit more weight and oomph than females in my opinion. 

Upper-Mids

Females are emphasized a bit more than males but aren’t overly emphasized at all. Depending on the singer and the track, females generally come across smooth and not too aggressive or too energetic. The S12P does a great job of portraying female singers with a good amount of charismatic expression to sound authentic yet without a great deal of shimmer. If that makes any sense. Closer to lush and smooth than they are lustery and gleaming. The sentimental softness portrayed in the song “The 1” by Taylor Swift has nice resolution while highlighting the cadence and emotion of her voice pretty nicely. 

Subtle cons

I don’t hear anything really glaring as a definitive con, except on rare occasions there is the faintest bit of planar timbre peeking through. This is also induced by my brain concentrating and listening for it. That being said I think females have a nicely positioned and energetic sound which is capped by a smooth delivery.  

Instruments come across with thin to average note weight but with nice layering of sounds. Strings, percussion etc. aren’t perfectly natural sounding but I hear nothing that sounds all together unnatural. This seems to be the case often for planar iems.

S12 Pro is pretty nice

Vocals are a very important part of my leisurely listening and enjoyment. I can verify and attest that the S12P is pretty nice in this regard. Perhaps a hair held back in the upper mids and a hair recessed in the lower mids, but there is a nice resolution and energy to make up for it in both cases. Also, sibilance is so minor that I didn’t even spend time on it. There is no real shout or ear gouging peirce in the upper-mids for me personally, but I’m sure that some may regard the S12P as too much. All in all, Letshuoer did a fine job in the Midrange. 

Treble

The treble region plays nice for the most part. I don’t hear anything fatiguing or shouty or sibilant here either. The treble is represented pretty well actually. I hear enough energy up top to balance out the spectrum without crossing over into shrill. That said, the treble can also be a bit underwhelming, to a degree. Yet in the very same breath the output up top may be too much for some. You can’t please everyone. I’ve heard both complaints prior to writing this review. We are an odd bunch aren’t we… we can never agree on anything. 

The treble is quick…

As you may have guessed, this treble is quick. “Bishop School” by Yusef Lateef shows off the treble region on the S12P. One of the tracks I use to test treble response. The S12P handles the fluctuations from percussion to strings to brass with partitioned off separation allowing a distinction between them all without blending the sound into a fusion of mush. 

As far as timbre goes the S12P isn’t too far off. Not the most natural sounding to my ears but also the S12P isn’t really plagued too badly by a planar metallic tizz at note ends. Cymbals & HI Hats trail off with good transient behavior and with enough authenticity to allow the atmosphere to develop and decay. Nirvana’s “In Bloom” begins with a deafening electric guitar riff and is topped by peppered-in cymbals that can easily become lost to the chaos surrounding them. However the S12P illuminates them pretty nicely with average weight while not sounding too splashy or attenuated. 

Treble balances everything nicely

Technically I think the highest regions come across articulate and detailed enough to cast light upon the minutiae and subtleties in most tracks with enough speed even in the midst of complicated songs. Extension is good as well, but it doesn’t extend in a full-on lustrous manner. More so, the treble simply upholds the rest of the mix. S12P highs never dominate and never really jump ahead of other frequencies. They actually balance everything out pretty nicely. There is some brilliance up top, and you will hear a sparkly playback from time to time but for the most part the treble is more reserved. 

Soundstage/Separation/Imaging/Details 

Soundstage

The Soundstage to me is nothing special or colossal in size. I hear mostly average all the way around, for the most part anyways. There seems to be an above average height and decent depth with an average width. I don’t feel the stage hinders the performance of the S12P as I get good contiguous spatial cues that create an appropriate and even good mental image. For those who drool over a huge stage though, the S12P will likely not be too impressive. Personally, I have zero issue at all with how large or… not large the stage size is. 

Separation/Imaging 

I have no problem discerning elements of the stage. Depending on the track, I hear well placed and distinct instruments and voices as separation is certainly above average for me. To go along with good separation is also very good imaging. Likely due to the speed of the driver, good resolution and clarity among other attributes is the reason that most elements of a stage are distinct and in their own localized position both side to side and forward and back. 

Details

I wouldn’t call the S12P the best in the price range when it comes to focusing on details, but it certainly is much better than your average earphone. There isn’t much which gets left behind with this particular tuning and the ability of these drivers. All throughout the spectrum details in my music are present. I definitely would not refer to the S12P as ‘top of the heap’ against a field of very nice iems but I also wouldn’t rate the S12P very far down on the list. 

Like I said earlier, stuff like breath against a mic, finger scrapes or the trail-off from an acoustic guitar. Even some of the finer details come through very nicely in less than complicated tracks. Tracks which involve most of the spectrum can slightly fog the finer details a hair. It isn’t that the S12P cannot keep up or isn’t resolute enough to zero in on the minutia either.  It has to do with the V-Shaped tuning where some areas of the mix simply overtake the finer stuff. All things considered, the S12P do details nicely while catering to other aspects of musical enjoyment as well.

Comparisons

TRI I3 Pro ($169 – $199)

The TRI I3 Pro or “I3P” as I will refer to it, is absolutely one of my favorite iems at any price point. It isn’t for everyone but honestly…what is? Something about this set just resonates with me. In some ways this is not a very fair comparison and in other ways it is a very nice measuring stick for the S12P. Of course, I never add a comparison with competition in mind. All comparisons are simply to help explain in a comparative way the device I am reviewing. 

The I3P are a Triple Driver ‘Tri-Brid’ iem consisting of a Dynamic Driver, a Planar Magnetic Driver and a Balanced Armature Driver. The sound of the I3P is a mild V-shape with deep basses, a melodic and smooth midrange as well as a brighter and airy treble region which never goes to fatigue. 

Low-end

Starting with the low-end I can easily hear that the I3P carries a much deeper and more guttural sound which has a bit more authority and tactile haptic rumble than the S12P. Now, the S12P arent very far off. I would say that the S12P full range Planar pitted against the dedicated low-end DD of the I3P is really not a very fair fight if deep basses are what you are after. The places where the S12P excels over the I3P is in the swiftness of transients and the details brought out in its playback. There is very nice texture on both iems but the more technical replay does come from the S12P. The I3P simply has that authentic Dynamic Driver timbre that seems to resonate just a bit better to offer a more atmospheric and satisfying listen. This is a question of preference, however.

Mids comparison

The low-mids of the I3P have a thicker timbre as male vocals have a bit more heft to them while the S12P are the slightest bit leaner. Truthfully both of these iems are very similar in the low mids. The I3P are just a bit less dry and just as transparent. As far as female vocals go the S12P are more forward and have a bit more shimmer and lean energy while the I3P are noticeably more robust in timbre and rounded in presentation. There is simply a fuller male and female vocal on the I3P. 

Treble

The treble region follows much of the same story. The I3P are bigger in note weight with a warmer tonality, fuller, while the S12P have a slightly thinner but possibly more detail-oriented sound. Both iems present technicalities very nicely with two very different tonal expressions. S12P have more dryness with an airier sound and the I3P are warmer, more syrupy and fuller and more robust. Both have nice resolution and clarity. 

Both have good space to operate, and neither are congested or veiled. These are two awesome options in the world of audio at this price point. 

Raptgo Hook-X ($239 – $259)

Stiff competition

The Raptgo Hook-X is currently one of my favorite Planar Driven iems on the market that I have actually listened to. There are quite a few that I have not so… take that with a grain of salt. The Hook-X came out just after the 7Hz Timeless had officially disrupted the audio narrative of what a planar iem can sound like. Everyone clamored to get thier hands on the Timeless. I know because I was one of those people. Then out of nowhere this relatively no-name company (Raptgo) came forward with the Hook-X and trumped the Timeless in almost every regard sonically, fitment wise, looks, the whole nine yards really. Of course, it is also a bit more expensive than the Timeless, and much more expensive than the iem I am reviewing today (S12 Pro). 

The Hook-X is a dual driver hybrid using a Planar Magnetic Driver and a Piezoelectric Driver and does so with a fantastic tuning. I would also call the Hook-X a V-shaped iem with a very dynamic and expressive approach having an emphasis in the low-end and the upper-mids to treble. 

Some differences

As for some differences that I can spot… starting at the low-end, the Hook-X has a sharper and deeper low-end with better texture and better resolution in my opinion. It also has faster transients with a snappier and tighter attack and quicker decay/sustain. The S12P are a tad slower but also the bass is a bit more cohesive in sound with the rest of the mix. The comparison graph doesn’t show what I hear at all as the Hook-X are a little more growling & gravellier with bass guitars and hit with more authority on bass drops. I don’t think it is by a country mile or anything but there is a difference. The S12P simply have a softer bass note without lacking in authority. 

Vocals

The clarity of the Hook-X shows up cleaner and more transparent then the S12P to my ears. This goes for male vocals as well as females. Details are more easily heard on the Hook-X with a more heightened and airy sound, but also a less natural timbre to my ears. The midrange sounds more forward on the Hook-X to me with more shimmery resplendance to females vocals.

The treble region of the S12P is a bit held back compared to the Hook-X, but again I hear a more cohesive sound altogether out of the S12P. Details are more readily available and illuminated by the Hook-X but possibly at the expense of timbre. Again, if the graph was telling the story I would be reporting the exact opposite comparison here. This shows us that planar magnetic iems don’t always perfectly graph the way they sound and to a lesser degree other driver techs can reveal similar findings. 

Overall

The overall tonality of the Hook-X is brighter and note weight sounds the slightest bit thinner and this affects every area of the mix. The S12P is more balanced in its approach with a more laid-back treble region, a hair more recessed midrange and a bit less oomph in the low-end. Absolutely the Hook-X is the more exciting listen but also maybe more fatiguing over time. I do think the Hook-X has better resolution throughout with a wider soundstage, better separation and imaging and more control of the music replayed through them. This would be a very tough choice for me because these both have so many redeeming qualities. Both fantastic planar driven iems. I have zero idea which one I like better. I suppose whatever one is in my ears at the time. 

Conclusion

I’ve had plenty of time to enjoy the S12P, enough time to know that it’s a keeper for me. The slightly colored balance between the frequencies is something I’ve really grown keen to. I like the dynamism, and the “close to DD” like nature of the low-end coupled with an easy going yet energetic treble region. The look of this set is great, from the earphones themselves all the way down to the rad looking modular cable. Furthermore, the choice of colors evokes a sense of poised masculinity due to the blueish/purplish hue and stainless-steel accents…it just looks tough. I think it’s the best-looking iteration of the “S12 Line”. Anyways, I don’t want to re-hash this entire review. I think Letshuoer is on the right path, and I will be sure to follow them closely in the future.

I am only a fan of music and the gear which replays that music, much like every other reviewer that I know. Also, just like every other reviewer, I only give my honest opinion of what it is that I hear and really try to explain to the best of my ability exactly what those opinions are. That said, I want to urge anyone possibly looking into the S12P to check out those other opinions from other reviewers. As I always say, we all have different libraries of music and different gear and different likes & dislikes and we may even have different abilities to actually hear what It is that we are listening to. Please listen, or watch, or read other perspectives in the community which may help you in making a wise purchasing decision. I truly hope that my experience helps at least one person.

So that’s it for my review of the Letshuoer S12 Pro. Now that the critical listening is complete I will actually try to leisurely listen so that I can enjoy this most awesome hobby that we are all wrapped up in. Please take good care and stay safe everyone.