In this article, I’m checking out the Letshuoer S12 earphones. The S12 features a custom 14.8mm planar magnetic driver and a minimalist industrial design. It’s priced at $152.

Disclaimer: This sample was provided by Letshuoer for an honest review. All observations and opinions here are my own based on my experience with the product.

Letshuoer S12

Specifications

• Impedance: 16Ω
• Frequency response: 20Hz-20kHz
• Sensitivity: 102dB
• IP Rating: IPX3
• Price: $152

What’s In the Box

• Letshuoer S12 IEMs
• Foam, standard and clear ear tips in S/M/L sizes
• Cable: 3.5mm single-ended / 4.4mm balanced connector
• LETSHUOER faux-leather case
• User manual

Design

Letshuoer has gone for a minimalist industrial design for the S12. The aluminium alloy shells have a smooth matte finish that’s free of any decorative flourishes. It’s available in either frosted silver or nebula grey colour plus you can choose between a 3.5mm or 4.4mm cable termination.

There’s a single vent near the base of the nozzle. The nozzles are fairly short but I found that they hold eartips firmly in place, even ones with a wide core. Once again, we see Letshuoer going with 2-pin sockets and the same monocrystalline silver-plated cable that comes with the Tape Pro albeit with a different termination.

The cable is thick but it’s supple and handles really well. It doesn’t get tangled and feels premium in the hands. This is one of my favourite entry-level/enthusiast cables and one of the better ones you’ll find included with IEMs in this price range.

Sound

Gear used for testing includes the Shanling UP5, xDuoo Link2 Bal, Cayin RU6 and SMSL D-6 with my Feliks Audio Echo tube headphone amplifier.

As much as I appreciate the S12’s aesthetics and cable, it’s the sound that stands out the most. Balance is the name of the game here and while the S12 isn’t strictly neutral, it delivers a relatively uncoloured sound and accurate tone.

Planar IEMs are known to have good resolution and speed and that’s just what the S12 delivers. It’s a strong performer when it comes to technicalities but it doesn’t sacrifice musicality either.

S12 is fairly efficient and can be driven sufficiently straight from a phone or a low-powered source. However, it scales well with gear so I’d recommend using a nice DAC or DAP to get the best results.

Bass

S12’s bass has typical planar driver characteristics: it’s fast, controlled and textured. Bass notes hit with authority and slam. The sub-bass extension is good with the lows reaching way down deep. A natural decay conveys a sense of weight and strength.

The bass is what I would call engaging without being overdone. It has clean leading edges, and ample punch and is moderately boosted in quantity. Notes are rounded enough to sound natural but the driver is fast enough to keep pace with anything you throw at it.

It’s a fun bass that lends body to the overall sound without any bleeding into the mids. It’s the tightness and speed of the transients that ultimately create the spaciousness and open stage. Playing through Porcupine Tree’s “Harridan”, you can clearly hear the texture of the bass guitar alongside the punch of the kick drum while the S12 effortlessly keeps pace with the track.

Midrange

The S12 presents a mostly neutral midrange, bolstered slightly in body by the size of the bass. You’ll notice the clarity immediately but there’s an underlying warmth there too. It’s this touch of warmth that gives the mids their fullness and natural feel.

Vocals are positioned slightly forward in the mix but with a neutral stage position: it sounds as though you’re in one of the front rows at a concert but not so close that you have to crane your neck to see the action.

Both male and female vocals sound equally impressive: they’re clear and articulate yet rich and natural in tone. Instrument timbre is spot-on: neither oversaturated nor dry. Everything just sounds pretty much “right”. It’s not entirely accurate but it’s a great blend of musicality and crispness.

Treble

The S12’s treble brims with energy and sparkle. It might be too edgy for treble-sensitive people but for my preference, it’s nearly ideal. There are moments where the treble sounds a tad thin but those moments are few and far between.

The detail retrieval is above average but not best-in-class. However, it doesn’t feel lacking in any way, especially for something in this price range. The treble tuning is an integral element of the overall tone and I think it strikes just the right balance with the bass and midrange.

Soundstage and Technicalities

The soundstage is average in size. It’s reasonably wide with moderate forward depth. What makes the S12’s stage special is the fast transients and clean air between instruments; something that planar drivers are particularly good at.

The detail retrieval isn’t best-in-class but I still consider it to be very good. Imaging is fairly strong, and the S12 is adept at creating layers within the music.

Sources and Pairing

The S12 is not fussy about which source you use but for this specific IEM, I’m adding this section by special request. I tested the S12 with 4 dongle DACs: Cayin RU6, Shanling UA5, xDuoo Link2 Bal and Moondrop Dawn.

All of the dongles pair nicely with the S12 but (unsurprisingly) my favourite pairing was with the Cayin RU6. I just like the synergy with this pairing: the sub-bass rumbles nicely and treble notes are crisp yet airy and ethereal.

The xDuoo Link2 Bal sounds great too and was the closest in performance to the RU6 with this IEM. Switching over to the Shanling UA5, I love the bass extension but to my ears, it sounded a tad brighter in the treble. That was a bit of a surprise because I would normally consider the UA5 to be a neutral/slightly warm DAC.

Finally, the Moondrop Dawn is also a nice match for the S12 (assuming you have a 4.4mm cable). With the Dawn, the sound is spacious with great instrument separation but the bass extension isn’t quite as good as the other dongles.

Comparisons

7Hz Timeless

The 7Hz Timeless is another planar magnetic driver IEM. It has a 14.2mm driver compared to the S12’s 14.8mm one. I know what you’re thinking when you look at the graph above: these 2 IEMs sound the same! Nope. Well, maybe a little bit.

The tonality of the TImeless is not all that different from the S12. But the small disparities make all the difference. First of all, the Timeless has a little less authority in the bass. It has a lovely, tight bass but the S12 has a little extra weight and oomph.

The midrange notes are leaner and have faster transients on the Timeless. As a result, the Timeless has superior resolution and separation. This is about as resolving as it can get for less than $200. But the S12’s slightly slower and rounder notes simply sound more natural. Furthermore, the Timeless is more prone to sibilance.

To my ears, it’s the treble that is the defining factor between these 2 excellent earphones. The Timeless has more upper treble lift compared to the S12 which boosts the core treble (7-10kHz) more. As a result, the Timeless gives vocals, percussion and some instruments a slightly unnaturally sharp leading edge – the detail is exquisite but it doesn’t sound entirely natural.

On the other hand, the S12 has rounder notes, a slower (and more natural) attack, especially on percussion instruments and ultimately sounds more musical. The Timeless is also more prone to sibilance.

Perhaps the starkest difference between these 2 IEMs is in the soundstage: Timeless’ presentation is very wide but it’s seriously lacking in depth. The end result is a very 2-dimensional stage that’s seriously deficient in depth and ultimately sounds unnatural.

In my opinion, there’s just something not right about the Timeless’ sound. The technical performance is outstanding but the overall result simply lacks engagement for me personally. Listening side by side with the S12, the S12 gets my vote every single time.

When it comes to the physical design, both are great. The Timeless is far more comfortable than it looks. But I much prefer the smaller, more inconspicuous design of the S12.

Raptgo Hook X

The Hook X is another single planar driver IEM. It features a 14.2mm driver (likely the same one found in the 7Hz Timeless). In addition to the planar magnetic driver, the Hook X also has a Piezoelectric driver.

The Hook X has a little added bass emphasis, making it a really fun IEM to listen to. Like the other planar IEMs in this review, it performs exceptionally well when it comes to bass response and transient speed.

The midrange is lovely; vocals sound sonorous and natural, upfront and visceral. Instrument size is just about ideal and overall it simply sounds great. The instrument separation and resolution are fantastic.

I like Hook X’s tuning and tonality: it’s a fun IEM with good technical ability. However, just like the Timeless (above), the Hook X’s sound is a bit unnatural, due to the resonance and ringing of the piezoelectric driver.

It’s slightly warmer than the S12 in the bass and midrange but is a tad edgy in the treble. The core treble is fine but the piezo driver has an unnatural ring to it that I find persistently distracting. It also causes some discomfort at a higher volume.

Physically, the Hook X is fantastic: it’s really nicely built and is comfortable in my ears. The cable is a treat too: fabric braided, colour matching with the IEMs and most notably, modular.

The Raptgo Hook X is a great IEM but I think the S12 at approximately $88 cheaper makes more sense. If it weren’t for the occasional piezo ringing, it would be harder for me to choose a winner but as it stands, I prefer the S12.

Verdict

The Letshuoer S12 is a standout IEM at the entry/enthusiast level. It’s smaller and more comfortable for my ears than the Hook X and Timeless. I am a big fan of the included cable and the other included accessories are all solid as well. But it’s the sound that really seals the deal here.

This is one of the best performing IEMs under $200 regardless of the driver type. I think anyone but the treble-sensitive will love the sound and the quality of the overall bundle is just a bonus. I was sceptical at first but after spending time with the S12, I’d say the hype is absolutely justified. In fact, this one is going on my best IEMs list. Highly recommended.