Pros –

Beautiful transparent shells with innovative pressure-relief, Spectacularly accurate timbre throughout, Hugely resolving midrange, Fast and extended BA bass with tasteful emphasis, Flat impedance design is easy to drive

Cons –

Dainty stock cable, Limited accessories, Treble doesn’t have much energy or sparkle

Verdict –

Combining hugely impressive timbral accuracy with top-level resolution, the RS10 provides a sound that has surely secured itself as a benchmark for years to come.

Introduction –

Moondrop is the name on everyone’s mind but their premium division, Soft Ears, are far less frequently discussed. This is not for lack of expertise nor success, as the company has only just recently expanded into the international market. I previously reviewed the RSV that I found to be one of the most impressive monitors on the market, a beautiful showcase of the company’s mastery of tonality. The RS10 builds upon the same reference sound platform and is currently the top model in their reference line alongside being their latest flagship. It houses a huge number of technical innovations and offers superb tonal refinement, taking the knowledge and technical expertise of the company to its pinnacle. Of course, its intended use case as a reference monitor should speak volumes for the type of sound tuning one should expect.

The RS10 is currently available for $2099 USD. You can read more about it and treat yourself to a set on Soft Ears.

Disclaimer –

I would like to thank the team at Soft Ears very much for their quick communication and for providing me with the RSV, RS10 and Cerberus for the purpose of review. All words are my own and there is no monetary incentive for a positive review. Despite receiving the earphones free of cost, I will attempt to be as objective as possible in my evaluation.

Contents –

Specifications –

  • Drivers: 10x BA drivers per side + 1x passive BA
  • Crossover: 15-component, 5-way
  • Impedance: 25 ohms
  • Sensitivity: 100dB
  • Frequency response: 20 Hz – 40 kHz

Behind the Design –

Custom Drivers With 5-Way Crossover

In addition to sporting a prolific 10xBA drivers per side, Soft Ears leveraged custom drivers as well that enable them to hit a more specific frequency response target and distortion characteristics. More drivers mean more complexity, so such a setup doesn’t guarantee a better sound, but theoretically has the ability to sound much better than a lower driver count if properly executed.

Of course, Soft Ears have implemented many techniques to optimise the sound output of the RS10, and this is a hugely well-considered design altogether. A 15-component, 5-way crossover has been used in order to achieve their desirable frequency response. Soft Ears take this one step further by tuning the time domain achieving almost linear phase across its 10 drivers. This was achieved using 2 band pass, 1 low pass and a 4th order LC filter.

Passive Driver + Pressure Relief

There are many challenges when designing in-ear monitors, one that is becoming increasingly spoken about is pressure relief. Increased wearing pressure is an especially large issue with in-ears as they form the tightest seal with the ear canal. This can alter the perception of sound over time via the tympanic reflex that results in decreased sound transmission to the inner ear – effectively reducing the perception of dynamics, bass and treble and resulting in a much less resolving sound.

 Competitors append this using valve or membrane which relieves pressure at the cost of isolation and bass slam. Soft Ears have used a unique approach, using a passive 11th BA driver with no motor structure. This allows the driver’s diaphragm to move freely and dynamically relieve pressure from the ear canal. In addition, it serves to enhance the driver surface area available, pertinent for bass response. This is a very clever approach as there is no drop in isolation or seal and you get an overall more efficient sound reproduction system. 

Ultra-Low Impedance Fluctuation

Another common weakness of in-ear BA design is their sensitivity to source output impedance. Soft Ears designed this earphone to have an almost flat-impedance curve, enabling a consistent sound across sources with differing output impedance. This is a great tool for professionals especially where interfaces may have a higher impedance. It means you reap the benefit of BA-driver efficiency without the touchy source pairings. 

Unboxing –

There isn’t much to say about the unboxing experience and it appears not to be of highest priority here. The buyer receives a small hard box containing a round leather case. Insides are the earphones within suede pouches that keep them pristine during shipping. A microfibre cleaning cloth is just below. The cable and ear tips are in a separate box, you get 3 pairs of silicone tips tuned to the fit-depth and nozzle size of the RS10. I did enjoy the tonality and seal of these tips and used them for this review. Otherwise, the buyer receives a nice metal Soft Ears business card but no other accessories. I am not personally bothered by this, but I can understand some wanting a more lavish experience from such an expensive product

Design –

While we’ve seen no shortage of 3D-printed clear shells pop up lately, the quality Soft Ears was able to achieve is mind bogglingly good. Even pixel peeping macro shots on the RS10 reveals zero bubbles or contamination. While one could argue for a premium metal shell at this price, the solid-body resin shell here is a thoughtful showcase of the earphone’s inner beauty; the 11 balanced armature drivers, four acoustic chambers and 15-component crossover mean the earphone is just as much of a pleasure out of the ear as within. With a transparent shell, Soft Ears’ design and workmanship is on full display, rarely do I see such a high level. The design cues also draw a parallel with the transparency of its sound as a reference monitor, altogether a smart design with perfect execution.

Above are 0.78mm 2-pin connectors lauded for their ubiquity, permitting wide aftermarket support. The stock cable is of pleasing quality and is similar to those you’ll find on the latest Moondrop IEMs. It’s a silver-plated copper unit with super-high strand count and clear jacket. It has an internal braid which means you get a little more microphonic noise but nothing excessive due to the over-ear fit. The cable is very soft, my main complaint would be that it’s a little thin above the Y-split. Otherwise, it impresses with its chrome connectors with laser etched Soft-Ears logos and thin, case friendly 3.5mm plug with strain relief.

Fit & Isolation –

The RS10 has a similar silhouette to the previously reviewed RSV making it slightly squatter than Moondrop’s resin earphones. The RS10 is identical in shape to the Cerberus meaning it has a slightly wider and more squared off shell relative to the RSV. It remains very smoothly formed, creating a snug fit but without excessively sculpting the anatomical features to maximise compatibility with a wide range of ears. In turn, I found them comfortable to wear for hours on end with no hotspot formation. The nozzles are of medium length so the fit depth isn’t too deep, remaining quite comfortable.

As the nozzles are well-angled, I achieved an excellent seal and rock-solid fit stability. Combined with the dense resin-filled shells and fully sealed design, the RS10 provides excellent noise isolation suitable for loud environments. The pressure-relief passive driver does also improve the experience here. It does indeed alleviate some wearing pressure well, and you will notice this in daily use through a more comfortable wearing experience, especially over longer listening, and less “thud” from footsteps when listening during commute. I was surprised how effective Soft Ears solution was as it comes with zero compromise to isolation or seal.

Next Page: Sound & Source Pairings

Sound –

Testing Methodology: Measured using Arta via IEC 711 coupler to Startech external sound card. 7-9KHz peaks may be artefacts/emphasised due to my measurement setup, less so with deep fit. Measurements besides channel balance are volume matched at 1KHz. Fit depth normalised to my best abilities to reduce coupler resonance. Still, due to these factors, my measurements may not accurately reflect the earphone or measurements taken by others.

Tonality –

The RS10 is about as linear as an upgrade as one can get in relation to the RSV and the lower Moondrop options such as the Variations. This earphone epitomises linearity and timbral accuracy, in turn, expect a little less sub-bass oomph than the RSV and Variations, nor much warmth and euphony overall. The RS10 is defined by surgical control throughout, excellent definition and a faithful representation of music in almost perfect balance. Despite this, the RS10 leverages profound technical ability, able to engage the listener with its ability to effortless finesse micro-details from complex tracks. There are 2 chief areas of colouration, that being the small bass shelf and small upper-mid hump. I feel both are in good taste as they are very small in the order of 2dB or so. Compared to a pure DF-neutral IEM like those from Etymotic, you will notice a little less separation in the bass. However, those earphones are quite unforgiving, the RS10 being more versatile.

Bass –

At a surface level, the bass performance is what can be most appreciated on the RS10 and this applies both to its tuning and its technical performance. This is a splendid combination between a clean sub-bass boost that doesn’t over colour the linear, hugely textured mid-bass and timing that would please a metronome. Extension is exceptional for a BA monitor; it has great slam and even a tight, satisfying pressure at the very bottom. Most impressive the is the quality of the sub-bass, very rarely do you hear such a defined and controlled rumble. While the note presentation means this won’t be mistaken for a DD earphone, I never felt slam, power or rumble were missing in the slightest. The note timbre is also highly accurate with a dead neutral tone. Note size is a touch enhanced and notes are emboldened due to the sub-bass tuning, though tasteful levels of emphasis ensure muddiness is absent entirely. The RS10 is a paragon of finesse and precision with regards to its bass quality too.

Attack is quick and concise whilst decay is a touch longer than your usual BA earphone. Note definition on a whole performs at the highest level which, alongside its extension and linear tuning, means you get unyielding resolving power of minutiae throughout the entire low end. Due to these properties, the sub-bass lift doesn’t overly affect separation and the earphone is able to upholds perfect composure on the most complex tracks. Naturally, earphones with zero bass emphasis do have a small advantage here, but to reiterate, this is hardly a con on the RS10. In addition, its notes are well-bodied and textured forming one of the most articulate and responsive low ends I’ve heard. The RS10 has a winning combination of quality and wicked clean tuning that will find wide appeal. The best dynamic driver earphones sound a bit more visceral and powerful at the very bottom, perhaps a lick more textured in the mid-bass. However, the RS10 is an outlier when it comes to both timbre and detail retrieval, getting amazingly close from a lightning-fast all-BA setup.

Mids –

Unsurprisingly, a similar impression is to be had with regards to the midrange. While the bass performance is easier to appreciate, it is the midrange that truly excels under scrutiny. For the RS10 is defined by its top-level tonal transparency and superbly even-handed voicing that flatters all genres and frequency ranges equally. The voicing is highly natural, and its timbre leaves basically nothing to be wanted in terms of consistency between mastering styles. The only colouration in sight is a lick of upper-midrange emphasis in the realm of a handful of dB around 4 kHz. This contributes to a slightly more revealing sound and brings vocals a touch forward. Due the linearity of its sound below in conjunction with a seamless bass/midrange transition, I didn’t find this to introduce strain, dryness or thinness. That said, this means the RS10 does sound a touch forward and some intensity can be heard at times, especially with regards to vocals.

This will not be to everyone’s tastes, but I found the small emphasis to be innocuous enough not to harm the RS10’s versatility. Certain tips such as Spinfits can also be employed to attenuate this region slightly to preference. Besides this, the RS10 is a truly stellar performer in all regards that easily hangs with the best. Midrange resolution especially is among the best I’ve heard. While the tonality surely contributes to its discerning nature due to its exceptional cleanliness, separation and clarity, the RS10 goes beyond the surface level with incredibly apparent and well-resolved fine details. For instance, listening to Billie Eilish’s “bad guy”, rarely do you hear a monitor that discerns vocal harmonisations and, as strange as it may seem, mouth sounds like the RS10. It is able to surgically deconstruct the most complex tracks and capture the underlying emotion with a rendition that pays tribute to both artist and producer.

Highs –

With a tuning so similar to the lower-end RSV and Moondrop models (that I similarly lauded for its linearity), the difference lies in the RS10’s far more resolved background detail presentation that adds layers, space and overall immersion. This is in addition to its far superior ability to capture small details in the foreground. The RS10’s delivery simply sounds cleaner and more effortless. It’s a very natural step up in terms of technical ability with minimal tonal colouration. Treble is no more forward, but small details are simply more apparent and easier to discern, each note having superior separation and definition. The dead even, even slightly smoother lower-treble tuning ensures note body remains accurate and instruments are richly textured and delivered with a realistic timbre. Indeed, note attack is sharp and decay is a touch faster than neutral, but never truncated. Notes are beautifully constructed, well-considered from both a frequency and time response POV. In so doing, the RS10 lacks any semblance of brittleness whilst retrieving details extraordinarily well.

To sum it up, the RS10 is a versatility specialist, representing all mastering styles and genres of music faithfully. The background is jet black and spotless, though even then, background details shine through clearly with excellent extension and resolution. This contributes to a hugely layered presentation that retains a good amount of air and headroom. While sparkle isn’t highlighted, strong extension ensures micro-details remain well apparent. The RS10 operates at a high level here, but it is clear this is not a focus of this earphone, prioritising timbre and organisation which are more useful, even desirable in a professional setting. In turn, this does mean Soft Ear’s reference flagship doesn’t provide the instantly gratifying, high-energy presentation of something like the Fir M4 of Campfire Audio’s high-end monitors. The RS10 prioritises linearity and a super detail-dense foreground over flaunting huge sparkle and overt spaciousness but maintains the enthralling resolution and spatial characteristics one would expect from a high-end IEM.

Soundstage –

The RS10 has a modestly sized soundstage emphasizing focused, hyper-accurate imaging over overt space and immersion. Nonetheless, I never felt it was a limiting factor of this earphone. Width stretches just beyond the periphery of the head as does depth, forming a nicely rounded stage with a pleasing sense of dimension. Imaging is the highlight here, being ultra-stable and highly cohesive. The centre image serves as a rock solid anchor for a highly layered lateral and coronal spread. In addition, layers are defined and well-delineated. Accordingly, the RS10 has pinpoint accurate localisation and its resolving treble means directional cues from through perfectly clearly no matter how complex the track. Its composition does mean it lacks that ethereal, floaty character achieved by more coloured monitors. Still, while not quite holographic due to its darker background, the RS10 is reasonably multi-dimensional. Separation is another high point and cannot be faulted. It is resolving throughout and the sub-bass emphasis is in great taste so as not to encroach upon the mid-bass. If there’s one defining trait of the RS10, that would be its ability to equally flatter every element in the stage, in so doing, fine details are apparent as nothing is overshadowed.

Driveability –

The RS10 sports a 25 Ohm impedance and a 100dB sensitivity making it far less efficient than your typical all-BA IEM. Indeed, this one requires additional juice to achieve regular listening volumes. However, to simplify things, it does have an almost linear impedance curve meaning output impedance shouldn’t affect its frequency response.

Output Impedance Sensitivity –

Switching between the Hiby R6 (10-ohms) and Shanling M2X (1-ohm) revealed minimal shift in tonality besides colouration of the sources themselves. This is a great asset for the RS10 as it means you can run it off a wider range of sources and achieve more versatile pairings. While it does pick up source colouration and scales with more resolving ones, professionals or audiophiles with multiple sources wanting a consistent sound should find that here.

Driving Power

The RS10 requires more voltage than most IEMs to achieve the same listening volume. This means if you are a high-volume listener using a lower-power portable device or smartphone, a DAC/AMP or external amplifier may be required. Otherwise, the RS10 isn’t too demanding. I found that, beyond volume, bass remained extended and dynamic on less powerful sources such as my Xperia 5 II, I was just pushing the volume higher than usual. My desktop stack did provide a slight increase in sub-bass weight but nothing huge. More noticeable was the jump in detail and soundstage expansion. Given its resolving nature, I would recommend a resolving dedicated source to extract the best performance from this IEM. The RS10 isn’t too prone to hiss given that it isn’t especially sensitivity. On volume 0 with the amp circuit engaged, the RS10 was dead silent connected to the M2X, where more sensitive IEMs can pick up noise.

Suggested Pair Ups

I believe this is one of the easiest high-end IEMs to drive, especially considering how resolving and revealing it is. Output impedance isn’t a concern, it doesn’t require amplification to achieve a dynamic sound nor is source noise a prime concern. The main concern here would be volume output but this shouldn’t be a concern for average listening volumes. Wide synergy can be achieved due to its tuning, though you will want a linear source like the Topping 30-Pro or 90 stacks to best appreciate its tuning chops. Technically, it also scales well. Added warmth isn’t a bad thing, however, and the RS10 has plenty of separation to pair with tube or warmer SS amps well. On the flipside, sharper sources like the THX789 aren’t a concern as the lower-treble isn’t emphasized. I would be most cautious of older Sabre sources afflicted by middle-treble glare, but even then, I didn’t find this pairing polarising. The ease of driveability is a huge asset for the RS10.

Next Page: Comparisons & Verdict

Soft Ears Comparison –

RSV ($729): The RS10’s greatest rival is likely Soft Ear’s own RSV, a model with a very similar character at about a third of the price. Nonetheless, the company ensure you get what you are paying for, the RS10 also has usability features such as its flat impedance design and pressure relief driver that aid a premium experience.

Sonically, the RSV and RS10 are evenly matched. The RSV has slightly more sub-bass and its upper-midrange is smoother, permitting a more energetic lower-treble without additional fatigue. The RS10 comes across as more mature and grounded with less bass emphasis and greater separation. While the RSV has more slam and note weight, the RS10 has better extension and much more defined rumble. It is faster and more articulate in the mid-bass, with greater separation. The RSV has a slightly more laid-back midrange but is also slightly more articulate.

In turn, it’s a little more forgiving and slightly higher contrast. The RS10 comes across as clearer and one notch more revealing. It has better resolution and separation due to its more defined note presentation. Highs tell a similar store, the RSV is crisper and more energetic in the lower-treble, the RS10 has more note body and stronger fine detail retrieval. Above is where the RS10 pulls ahead having instantly superior background detail retrieval and much better imaging as a result. So while, the RSV comes across as equally tonally accomplished, the RS10 takes the technical performance to the next level making it a very linear upgrades for Soft Ears fans.

Cerberus ($2099): Soft Ear’s co-flagship with a tri-brid driver configuration and a mellower sound signature. This model is a valid alternative for those wanting a more laid-back and forgiving listen whilst retaining headroom and micro-detail. It has a similar pressure-relief driver but no flat impedance design.

The Cerberus extends slightly better, delivering a more palpable slam and more defined rumble. It’s slightly warmer and epitomises natural, controlled and textured DD note properties. The RS10 is noticeably faster and more articulate. It has higher note definition and is more detailed. The midrange tells the same story. The RS10 is more resolving, tonally cleaner and more separated. The Cerberus has a smoother upper-midrange and more body around the lower-midrange, trading off separation and note definition for greater coherence. It is well-textured and highly natural but not as focused.

Once again, the treble continues this trend. The Cerberus has a softer transient response but equally strong speed and slightly better extension. The RS10 has more bite and its notes are slightly more defined and separated. The Cerberus is daintier and more delicate, preferring greater body and texture. The Cerberus is slightly airer and has more headroom but the RS10 has better detail retrieval in all regards. The Cerberus does have a noticeably larger soundstage in all aspects. Its imaging isn’t as pinpoint accurate and layered, being more atmospheric and expansive instead. The Cerberus appeals to a very different listener than the RS10 and is equally valid as a high-end offering.

Comparisons –

Avara EST-6 ($1100): Avara’s EST flagships designed to provide an utmost linear sound, indeed it is highly natural and much cheaper. The RS10 has a more revealing and cleaner tuning while the EST-6 assumes a more forgiving approach to linearity. The RS10 extends better in the bass, possessing more power and rumble in addition to greater slam. The EST-6 has similar bass quantity but more focus in the mid-bass, instigating a slightly punchier, fuller and warmer voicing. The RS10 is more controlled and faster, offering a more articulate, defined note presentation with greater detail retrieval. Both earphones have a similar midrange tuning and voicing. The EST-6 is lower contrast, trading off some separation and tonal cleanliness for greater coherence.

It achieves this with aplomb, lacking any intensity. It is slightly warmer and roomier with more lower-mid presence. It is a touch more articulate, redeeming definition. The RS10 is cleaner and more separated with a more revealing character in general. It has higher resolution with more fine details. The EST-6 has a generally smoother treble but a small lower-treble bump for crispness. The RS10 has slightly sharper note attack, giving it better fine detail retrieval in the foreground. It is also a little airier. Meanwhile, the EST-6 has slightly more headroom and sparkle and its background is a touch cleaner. This contributes to a slightly larger stage though the RS10 does have noticeably sharper imaging.

Campfire Audio Ara ($1299): The Ara comes in at a cheaper price point and is intended as CFA’s flagship designed to deliver a HiFi sound. It has less bass overall but a slightly fuller tuning. The RS10 extends better, having more power and pressure in addition to greater sub-bass emphasis. The Ara has more upper-bass and lower-midrange presence which gives it a bit more structure, the RS10 being slightly cleaner and focused more on rumble and dynamics. The Ara has slightly longer decay giving it a more musical quality while the RS10 is faster, tighter and more articulate. The midrange is likely the Ara’s most polarising quality, being forward and revealing, it doesn’t sound as even or natural as the RS10. I wouldn’t call the Ara unnatural but in direct comparison, it does have a more coloured presentation. It is slightly more full-bodied but vocal size is smaller, sounding drier.

The RS10 has a more focused midrange presentation occupying a stronger centre image. It has better upper-midrange extension and a more accurate articulation especially. The Ara is higher contrast, with a smoother upper-midrange set to a brighter, more articulate treble. In turn, it does come across as slightly more revealing and textured than the RS10. Conversely, the RS10 discerns nuances better with a more coherent note structure and it has a more natural timbre. The treble is more even on the RS10. It has more body and slightly more texture while the Ara is slightly crisper, bringing fine details more to the fore due to its brighter tuning. The Ara has greater air and a modestly emphasised sparkle making it sound more energetic and open while the RS10 has a cleaner background with more stable layers. The Ara has a larger soundstage in all aspects while the RS10 has more accurate positioning. The Ara tends to push wide, the RS10 has a stronger centre image.

Lime Ears Pneuma (1800 EUR): The Pneuma has a similar style of tuning to the RS10 but a smoother upper-midrange that some may enjoy. The Pneuma appears slightly bassier on account of its less forward midrange. It extends slightly better in the sub-bass and has a little more warmth and note body, but not too much that it sounds overly coloured. The RS10 remains a noticeably cleaner performer with a dead neutral tone and more localised sub-bass boost. The Pneuma decays more naturally and has a textural and dynamics advantage. The RS10 is faster and more articulate, with better timing and separation. The midrange voicing is similar on both and I would consider both to be very natural. The Pneuma is slightly higher-contrast with a larger lower-mid dip counterbalanced by a denser upper-midrange and slightly warmer mid-bass. The net result is quite similar, the Pneuma has similar vocal positioning is slightly more coherent and less intense.

Meanwhile, the RS10 is slightly more revealing and resolving. The Pneuma is slightly more articulate, but as it is denser, it isn’t overly so. This means fine details are still flattered. The Soft Ears monitor has a more neutral tone and is slightly more linear. It is more discerning of fine details as it has higher resolution. The Pneuma has a small 5k peak to redeem energy with the RS10 being smoother and more even. Both offer a clean transient response, the RS10 has a slight resolving power advantage while the Pneuma benefits from a slightly crisper tuning. The RS10 has more air and headroom, the Pneuma has a little more energy in the foreground but not as much audible extension. The Pneuma has slightly more depth while the RS10 has a bit more width. The RS10 has noticeably sharper imaging.

Fir Audio M4 ($1899): Fundamentally, the M4 more U-shaped with greater emphasis on bass and lower-treble. It is noticeably bassier, extends slightly better, delivering more pressure at the very bottom alongside possessing greater warmth and fullness. The RS10 is a cleaner, more balanced sounding monitor. It has a neutral tone and is more articulate and separated. The M4 has excellent mid-bass texture and a more natural decay while the RS10 is more linear and discerning of fine details. The midrange presentation showcases a similar trend, the M4 being clearly more coloured but an equally natural listen. It is brighter and more articulate but also slightly lower contrast, picking up some warmth from its bass. Both are on the revealing side, the RS10 is slightly more forward but also more transparent in tone and note size in addition to offering a more accurate articulation. In turn, it has a more accurate timbre in general.

The two are close in terms of resolving power, but the RS10 overall does resolve texture and fine nuance slightly better due to its more linear tuning. The M4 has more defined layering in return. In the treble, the two continue to trade blows. Impressively, the RS10 slightly outdoes the M4 in the lower-treble. While the Fir is more sharpened and crisper, the RS10 has more body and texture, an edge in fine detail retrieval overall. The M4 above has more air, headroom and sparkle above, however, so it does have a bit more background detail. The RS10 has a darker, cleaner background, prioritising a more natural and focused detail presentation. The staging is of similar character, the M4 is wider but both are matched for depth. The M4 has more contrast between its foreground and background and images in a holographic manner. The RS10 isn’t so energetic but has more layers and its imaging is more stable with sharper direction.

Final Audio A8000 ($1999): The A8000 has a similar emphasis on cleanliness but executed in a brighter and more revealing manner. The A8000 has a similar balance, but slightly greater upper-midrange focus. Its bass tuning is incredibly similar, with just a little more mid-bass warmth. The Be DD provides greater extension and power, it has more pressure and a more defined rumble. The A8000 is a little fuller and punchier in the mid-bass while the RS10 assumes a cleaner character. The RS10 is slightly more articulate and separated, but the A8000 is immensely fast and snappy for a DD whilst retaining a textural and dynamics advantage. The midrange is the most polarising aspect of the A8000 as some find it quite intense due to its greater upper-mid presence. The RS10 does showcase better restraint here, upholding greater balance and, to my ears, a more accurate timbre.

The A8000 has slightly more body but also sounds a little strained and intense indeed. It has a sharper articulation on top which isn’t sibilant to me, but especially unforgiving. The RS10 is more balanced and less intense. It has higher coherence due to its smoother articulation and more even upper-mid tuning. Despite being less revealing in tuning, I find the RS10 more resolving in the midrange of fine details. The top-end is brighter on the A8000 as well, especially the lower-treble. It also has a darn sharp transient response meaning it is both crisp and highly discerning. The RS10 has a slight advantage here on separation and it has more accurate note body. This enables it to reproduce fine textures better and with less sharpness. The RS10 has a bit more air, the A8000 slightly more sparkle. The A8000 has a noticeably wider soundstage and both have sharp imaging. The RS10, being more balanced, separates better to me as it suffers from less top-end glare.

Verdict –

I unironically fist bumped the air when I first hooked the RS10 onto a solid source and booted up my favourite songs. The tonality is on point, it has TOTL resolution and, even with a pure BA setup, the bass is physical and deeply extending. Few earphones light up my dopamine like the RS10 but, as always, that does not mean it is for everyone. The RS10 isn’t fatiguing, but it isn’t an especially forgiving sound either. Similarly, its relative lack of colouration means those expecting huge energy in the upper-treble or a fun, warm bass will be left wanting. Conversely, the RS10 builds atop the RSV’s foundation, being a master of versatility, and this is a sound that the vast majority will find immensely impressive. Ironically, many high-end IEMs assume a more coloured approach to tuning, which isn’t a bad thing and can contribute to a more impressive listen. However, those wanting a reference sound with top-level technical ability have a relatively limited list of options. You very rarely hear such a fast, tightly woven sound that is so equally flattering of all musical genres and so resolving. The RS10 is the solution, combining hugely impressive timbral accuracy with top-level resolution to provide a sound that has surely secured itself as a benchmark for years to come.

The RS10 can be purchased from Soft Ears for $2099 USD at the time of review. I am not affiliated with Soft Ears and receive no earnings from purchases through this link.

Track List –


Billy Joel – The Stranger

Bob Seger – Night Moves

Cream – Wheels of Fire

Crush – OHIO

Daryl Hall & John Oates – Voices

Dire Straits – Communique

Dirty Loops – Next To You

Eagles – Hotel California

Fleetwood Mac – Rumours

H.E.R – I Used To Know Her

Jaden – BYE

Joji – Sanctuary

Kanye West – Donda

Maneskin – Chosen

Pink Floyd – The Dark Side of The Moon

Radiohead – OK Computer

TALA – ain’t leavin` without you

The Beatles – Abbey Road

The weeknd – After Hours