Miniature Big Planar With Even Bigger Performance

We are heading towards the end of 2025 in a blink of an eye and Kiwi Ears has so far been impressive nonetheless, with superb releases like the Astral, Septet, Ètude IEMs all the way to Ardor, Altruva headphones, they have surely stamped themselves to be one of the brands to look out for in the future. While planar IEMs have been rather quiet this year, it is good to have a look back over to 2024 when Kiwi Ears released their famed Aether Planar IEM and they are being hyped as one of, if not the best planar IEM in their price range. The big question is, is the Aether still a good deal in the ever growing audiophiles market? Today we will dive in the planar IEM that actually won Kiwi Ears a VGP lifestyle summer award, the Aether.

A huge thanks to Kiwi Ears as usual for the opportunity by sending us a sample of the Aether and no monetary transactions is given for this review for an honest take on these IEM.

Functions & Specifications

Before we start the review, here are the specifications of the Kiwi Ears Aether;

Features:

• Shell: 3D printed Medical Grade Resin body
• Sensitivity: 105dB SPL/mW (at 1KHz)
• Frequency Range: 20Hz-20KHz
• Impedance: 14 Ohm (at 1KHz)
• Driver: 15.3mm Planar
• Cable Details: 1.2 Meter 0.78mm, 4 Core OFC in 3.5mm Termination

The Kiwi Ears Aether can be purchased at their website and many other platforms around the globe.

Kiwi Ears Aether

Packaging & Accessories

The packaging here is rather unique to the other products of Kiwi Ears with a rectangular outer box that slides out in a lavish, almost metal like silver box and they do feel special indeed. Inside we are greeted with the Astral IEM head and the accessories that accompany it which includes a 4 core OFC cable in 3.5mm only, 9 pairs of eartips in various sizes, a zippered hard case and some paperworks. Pretty standard accessories but I wish the cable includes more termination choices and a bigger case will be welcomed.

Design

The Aether has a standard CIEM style of shell that is ergonomic and comfortable but it is on the larger side with a thick shell to accommodate the 15.3mm planar but they are still comfortable as they are ergonomically designed. It is a 3D printed medical grade shell in semi transparent black with handpainted faceplate adorned with an aluminum frame. The build quality here is really good with minimal seams and a glossy resin finish. The handpainted faceplate has glitter streaks in them with their branding on top and finished with a clear resin on top.

Inside of the Aether is where things get interesting as they are equipped with a large, probably the largest in IEM form till this day, 15.3mm planar magnetic driver that barely fits the shell as the round edges of the drivers can be seen on the outsides of the resin shell. Pretty impressive stuff to cramp in the large driver and they are tuned to give an immersive, wide sound with a low distortion that is speaker-like. The planar is a custom made driver specifically developed by Kiwi Ears and they have a multilayered N52 magnets design coupled with their large diaphragm to produce an almost headphones like sound experience with a rather high sensitivity to be driven easily.

The tuning of the Aether is an extensive process that Kiwi Ears has been working hard on to adhere to their house sound with a big, deep bass, a neutral flat midrange alongside an airy, natural high range that is true to life.

The nozzle here is made from aluminum alloy and has a 6mm diameter at the tip. They are fitted with metal mesh to prevent moisture and dust from entering.

The Astral has 2 pin holes small near the 0.78mm pin used for the back vent of the planar and another pinhole at the inner side of the shell to alleviate pressure. The Aether possesses no driver flex that usually plagues planar drivers which is a big plus for comfort and longevity of the drivers.

The cable included is 4 core oxygen free copper and only available in 3.5mm. The cable has decent quality and they are a practical cable but aren’t high end ones. The cable is soft and pliable that feels soft, suited for everyday use but a higher quality cable like the ones on the Astral or Septet will be awesome.

Gears Used for Comparisons

Songs list

Tone and Presentation

The tone of the Aether is a neutral warm signature that has its bass slightly lifted similar to the Astral and they are a highly musical pair of planars that has an almost natural timbre similar to a dynamic driver which is a big plus. They are a tonally balanced set of IEM with a mild lean towards a brighter sound with a mild V shaped sound and they are inoffensively tuned while still having a good amount of energy. The sound here is full and wide alongside possessing a wide dynamic range with great extensions on both ends producing an airy presentation.

Soundstage

The Aether soundstage is where the big planar effect comes in as the soundstage here is truly wide with a good height to them. The space that the Aether is able to give is expansive, almost rivalling some earbuds and they possess a rather big headroom that possesses no boxy feel with good sound placements. The accuracy here is great with a holographic soundstage that has a good 3D spatial awareness making them suited even for gaming and movies. The sound does project slightly outwards which gives an airier feel but they aren’t an intimate pair of IEMs albeit still possessing some intimacy.

Separation and Timbre

Separation is good on the Aether and this is one of the strengths of a planar driver as they possess a wide stereo width that separates the left and right without any crosstalk issues and they will scale up better with a balanced output. Timbre on planars has been known to exhibit an unnatural metallic sheen especially on the high range but it is safe to say that timbre here is one of the better ones best described as breathy, organic and rich that has little to no unnatural timbre but with some sources driven by Sabre based chipset that has the infamous hump, some metallic sheen can be audible.

Drivability

Rated at 14 ohms with a 105db sensitivity, they are easily driven with most of the source out there which is great for a portable, casual usage. The scalability here is actually great as they do scale up significantly when used with other higher end products and they do benefit from source matching as a bright signature based source might incur an unnatural timbre. They are a forgiving type as normal streaming or low bitrate files still sound decent but higher bitrates files do sound slightly cleaner and clearer as usual. The Asether is not exactly a revealing type of IEM but they are still able to show flaws in recordings but aren’t as perfect in terms of their transparency versus some studio monitors.

The Bass (Low)

The bass here is probably the best part on the Aether and they are nimble, dynamic and have authority when called upon. The bass here has a mildly boosted mid-bass region without having any bleed, bloat nor overpowering issues. Details and clarity here is superb as they are able to reproduce the entire low region in a clean and textured manner that shows the layers in the bass clearly. The bass here I would best describe as a quality over quantity and the amount here might also suit light bassheads but not for those serious bassheads who want an earth shattering amount. The sub-bass amount here is average and the mid-bass amount is more prevalent but it does have adequate rumble to prevent the bass region from sounding hollow. Sub-bass depth is great and they extend well producing a rather airy presentation.

The Mids

Midrange on the Aether is a neutral flat mids that is slightly recessed and they do slightly lean towards the high region to give a mild bright signature with a good amount of lively brilliance. The midrange body here is full and has a slightly thick body that is spacious. Details here are superb with the whole midrange sounded clear with great macros and a rather average but good micro details. Clarity here is great with a clean, accurate, highly transparent sound with a dash of colouration producing a good musical experience. The midrange has great resolving capabilities and the mids here is vivid alongside a mild coloration that preserves the accuracy of sound. Vocals here are decent, there is a good amount of brilliance in the upper mids and a great depth in the lower region producing a rather balanced vocal presentation but at certain times, vocals may sound a tad distant especially with live performances. Instruments sounded full and rich but on certain high range instruments like strings, they do display occasional metallic sheen to them.

The Highs

The high range here is a neutral to almost flat highs that is quite present producing a good bite into the music while giving no harshness, shout or peaks. The overall high range here has a good energetic presence that has a strong, lively sparkle that manages to sound smooth with a mild crisp decay and a good, airy extension. Details on the highs are great with high range nuances reproduced well with no sibilance while able to give a clean yet strong sparkle. The overall high range is clean and it is inoffensively presented even on high volume. Transparency here is good as they are an accurate high range albeit with a very minor metallic timbre but they do resolve very well in this region with vivid overall high range that is rather engaging. Treble here has a good intensity that gives the overall sound a clearer, livelier presentation that isn’t dull to listen too but for those who want a more laid-back type of signature might find the high range a little too aggressive but personally I do find the high range here quite enjoyable for their energy and bite that gives music some extra kick.

Comparisons

VS Letshuoer S15

The Letshuoer S15 has been released for more than a year now and it is still touted as one of the best in-ear planar magnetic earphones within their price range. The price has slightly dropped but still costs almost twice the asking price of the Aether. The packaging and accessories included on the S15 is way better but the fit on Aether is more ergonomic and doesn’t have driver flex like on the S15 albeit minor. Build on both are different with a matte shell with magnesium alloy faceplate on the S15 and the Aether is mostly resin built but both have great build quality.

The high region of the Aether is slightly more present and has a sharper, a little piercy sparkle that gives more bite into the music while the S15 does sound crisper. Details, especially micro details are better on the S15 but with similar clarity. Timbre does sound slightly better on Aether with less sheen marginally. Treble on the Aether does have more amount and extends better. The 15.3mm planar on the Aether does trump the 14.8mm planar driver in size giving the Aether an edge in airiness and a wider dynamic range.

Midrange both have a similar neutral flat signature but the S15 has a more forward approach and they aren’t recessed like the Aether. Details are slightly better on the S15 while clarity remains similar. Although having slightly recessed mids on the Aether, they have more space and air. Both of these sets are highly resolving but transparency isn’t their forte.

Bass quantity on the S15 sounds bigger but with the same amount of mid-bass lift but the S15 dives deeper along with a bigger sub-bass response in a small margin. Details and clarity of the bass is better on the Aether but the S15 does sound more immersive.

Soundstage on the Astral is wider with an airier presentation possibly due to the bigger driver

My pick: Aether as they are competent albeit a little less technical all in a lower price range.

VS Hidizs MK12 Turris

One of the bigger releases this year from the staple Chi-Fi brand Hidizs, the magnesium dynamic driver MK12 Turris. They cost roughly the same and have similar packaging and accessories but the Turris does have the pneumatic tuning nozzles for user optimization. The Turris is an all aluminum alloy shell that is hefty in weight and has a thicker shell but still quite comfortable although, I personally feel the Aether fit has a more snugly fit. Timbre is without a doubt more natural on the Turris with an organic, richer laid-back style but the Aether does have the planar capabilities of being more energetic, cleaner and wider in their dynamic range.

Highs on the Aether is stronger with a more aggressive presence along with an energetic and crisp presentation versus the flat, smooth highs of the Turris that is inoffensive. Details and clarity is also better on the Aether here along with more resolving highs but the Turris does have a more natural timbre without any metallic sheen. Extension better on the Turris marginally and airiness is similar.

The midrange of the Turris has a slight edge in resolution but clarity and details are better on the Aether. The Turris possesses a thicker, full bodied mids with a tad more colouration that leans towards the lower range while the Aether sounds clearer and cleaner with a more upper mid range brilliance. Vocals on the Aether sound livelier but a little distant while the Turris has a more forward mids but lack brilliance versus the Aether.

The bass quantity is actually pretty similar with the Turris sounding bigger and meatier while the Aether has a more nimble, quick bass with more energy. Details on the Aether here are cleaner and clearer while clarity on both are similar. The sub-bass on the Turris is deeper and possesses a bigger rumble.

The soundstage on both are similar with a wide, spacious sound that possesses great air but the headroom on the Turris feels bigger.

My pick: Aether as they fit my preference of having a more energetic overall sound.

Synergy

As for synergy, I do not recommend bright sources like some Sabre based chipset especially ones with the infamous glare as they will introduce some metallic timbre and the treble might get hot. A warm or balanced source from the likes of AKM, Cirrus Logic and some well tuned Sabre will give the Aether a smoother, lusher sound while keeping the energy intact. They are relatively easy to drive, giving ample loudness even with simple source but I do feel that they need a good, clean source with adequate driving power will scale the Aether up producing better overall dynamics and a more controlled, textured bass as well as smoothening the high range. As for file selection, the Aether is quite a revealing set of IEM that makes certain low quality sources like bluetooth and low bitrate tracks sound a tad compressed but still a great IEM for everyday usage. For monitoring purposes, it is doable but there are plenty of IEM that specialize in this area and the Aether is more of a fun, jovial kind of IEM.

Good matching: Moondrop MIAD01, Qudelix T71, EPZ TP35, Hiby FC6, Hidizs S8 Pro, Questyle M15, 7HZ Artemis39, FiiO Q15, BQEYZ Lin

Not so good matching: FiiO Q7, EPZ TP30, FiiO KA3, Dunu DTC100

Who Is It For?

The Kiwi Ears Aether is a superb choice for those who want to experience the pinnacle of planar  in an IEM form. It has all the good traits of a planar driver with their speed, richness, clarity and energy. They are a fun sounding IEM that possess high technicalities that will suit audiophiles and mainstream users as well. Their mild V shaped sound will match modern genres such as EDM, pop, hip-hop and even jazz but not so much for metal, JPop and harsh genres as the treble may get hot for treble sensitive users. For monitoring purposes, they aren’t a reference neutral type of sound albeit still accurate but they do show instances of unnatural timbre. The Aether suits an everyday carry IEM and is suitable even for workouts, gaming and movies for their comfort that has an immersive sound.

Final words

While the planar race has subsided as we are reaching towards 2026, it is clear that the Kiwi Ears Aether is probably the stand-out pair of planar IEM and it is my pick for the best planar in terms of price and performance besting out most of the planar in this price range. Having the big 15.3mm planar does give the Aether a big sound that has all the qualities of a huge, speaker like sound as advertised and being tuned masterfully by them, they are able to minimize the shortcomings of the weird planar timbre. Though it has some minor caveats, the end product here is simply super enjoyable and has the unique flair of Kiwi Ears that truly deserves the awards they have garnered. The Aether will indeed become a classic in the future.

I would rate this product a 4 and half stars over 5 stars.

Pros

• Great technicalities with superb musicality
• Solid build with great design
• Ergonomic fit with no driver flex
• Above average overall details and clarity
• Great separation, imaging and tonal balance
• Big headroom and wide soundstage
• Superb extensions on both ends
• Energetic, quick, authoritative bass
• Good sub-bass and mid-bass amount
• Clean and clear midrange
• Great amount of brilliance
• Highly resolving
• Energetic, sparkly high range
• Well extended treble
• Beautifully packaged
• Relatively easy to drive
• Superb planar driver value

Cons

• Big, thick shell to accommodate the 15.3mm driver
• Instances of minor metallic timbre
• Vocals a tad distant/recessed mids
• High range may lack crispness
• Not for treble sensitive users (subjective)
• Not for monitoring (subjective)Accessories can be better(nit-pick)