Kiwi Ears Aether

A Planar That Reaches for the Sky

The Kiwi Ears Aether is a new planar from Kiwi Ears’ and joins their expanding lineup. I think Aether is an interesting choice for its name as, means the “the upper regions of air beyond the clouds”. This name certainly gives this IEM tuning a lot to live up to.

I feel very fortunate to have had the opportunity to listen to many of the recent KiwiEars IEMs, with some of my favourites being the Astral, the Septet, and the Ke4. I felt each of these models was distinct enough to be unique but balanced in their own way, typically each following a slightly different “tilted” frequency response.

So, does the Aether take its planar driver to new heights and continue this tradition? So, having listened to the Aether for the best part of a month, I hope to answer that question in this review.

But first let’s look at the unboxing.

Unboxing and Build Quality

The Kiwi Ears Aether arrives in the familiar, elegant packaging we’ve come to expect from the brand:

The outer box features clean, professional branding with tasteful design elements that immediately convey quality:

The side of the box provides some information, especially the size of the Planar at 15.3mm is very impressive:

Removing the outer sleeve reveals a premium silver presentation:

Opening the internal box you see the documentation in a sleeve:

Removing the documentation:

Then underneath the Aether are finally visible:

I do like the silver finish on the various boxes It gives it a very premium look:

The Aether looks pretty nice in its box:

Opening one of these boxes reveals the now standard Kiwi Ears hard carry case:

Opening this case reveals the included accessories:

The cable quality is excellent as it has been with recent Kiwi Ears offerings:

With well-constructed 2-pin connectors:

And a decent 3.5mm connector, though pity it is not an interchangeable connector like I have seen in many recent IEMs in this price range:

The ear tip selection includes multiple sizes:

Each ear tip has a unique nozzle and slightly different shape, so a good variation to get the right fit:

Design and Build Quality

The Aether IEM shell showcases some excellent build quality and I love how it looks in the sunshine:

With a very distinctive shell design:

The faceplate design very nice with careful attention to detail:

The side profile shows the ergonomic considerations in the shell design:

The overall shell shape is well-executed:

The nozzle design is shallower than some of the other Kiwi Ears offerings, so slightly better for smaller ears, and I would rather have a deeper nozzle, but this can very subjective:

Fit and Comfort

While the Aether generally offers good comfort, though I did find it to be less secure in my ears compared to some other recent IEMs from Kiwi Ears. The shell design, while attractive, was more prone to becoming loose during extended listening sessions, especially when I went for a long walk.

This doesn’t significantly impact the listening experience, but it’s worth noting for those who generally like larger deeper fitting IEMs and find smaller / shallower fitting ones to be less secure as this is more the latter.

When compared to other Kiwi Ears models, the shell size and shape differences are apparent:

Here is a comparison of some Kiwi Ears IEMs faceplates:

As a different comparison, here is the Aether with other IEMs shows the Aether is a bit larger than average:

Sound Impressions

The Aether’s single planar driver configuration delivers a compelling sound signature that stands apart from other Kiwi Ears offerings. The tuning showcases what makes planar drivers special and why the name is a reference to air with some nicer technicalities while maintaining musicality across genres.

Bass

The Aether presents a more relaxed sub-bass approach that won’t satisfy dedicated bass-heads, but this restraint allows the lovely warmer mid-bass to truly shine. The mid-bass response avoids muddiness while providing satisfying impact and warmth that gives music a natural, organic feel. The planar driver delivers excellent control and texture, making kick drums feel substantial without overpowering the mix. With tracks like Daft Punk’s “Giorgio by Moroder,” the bass lines have great presence and definition, showcasing the driver’s ability to render both punch and detail simultaneously while maintaining that characteristic warmth.

Midrange

The midrange benefits from the planar driver’s inherent qualities, delivering vocals with excellent clarity and natural timbre. What I particularly love about the Aether is its slightly vocal forward midrange presentation, which reminds me a little of the beloved Kiwi Ears Orchestra Lite in this frequency range. The warmer tuning complements both male and female vocals beautifully, bringing them slightly closer to the listener without being aggressive. Artists like Norah Jones sound particularly engaging, with her vocals having proper weight and emotional connection. The midrange positioning creates an intimate listening experience that draws you into the music with that characteristic vocal presence that makes long listening sessions so rewarding.

Treble

Here’s where the planar driver technology truly shines, and where Kiwi Ears obviously wanted to show off the planar driver a little. The treble is beautifully smooth with a distinct touch of airiness that gives the Aether its ethereal character. The treble extension and detail retrieval are excellent, providing the kind of resolution you expect from planar technology while maintaining that smooth, non-fatiguing presentation. Cymbal crashes and high-frequency details are rendered with precision and that characteristic airy quality that makes the soundscape feel open and spacious. The treble complements the warmer lower frequencies perfectly, creating a balanced presentation that works across genres while adding that special planar magic to the upper frequencies.

Soundstage and Imaging

The Aether excellent channel matches help provide some excellent imaging, and its tuning does add nice soundstage width and depth especially for an IEM in this price range. Imaging is precise, allowing you to place instruments accurately within the soundscape. While not the most expansive soundstage in the Kiwi Ears lineup, it’s certainly adequate and well-proportioned to the overall tuning.

Specifications and Measurements

Technical Specifications

The key specification here is 105dB which makes it easy to drive even with an Apple usb-c dongle.

Frequency Response

I have measurements of the Aether (as well as many other IEMs) on my Measurements database here taken with my 711 clone coupler.

The frequency response measurements show the Aether’s tuning, I hightlight a few areas for discussion

1. Nice bass with a little sub-bass roll-off
2. Slightly warm mid-bass nearer JM-1 than the typical Harman ’tuck'
3. A midrange vocal forward tuning here, I typically like this approach, it balances that warmer mid-bass nicely
4. Mostly a nicely detailed treble, but you can see the upper treble (as the Aether name hinted) is elevated (to the heavens). This will sound very ’technical’ but might be too much for some people.

Overall, I like that Kiwi Ears are pushing the Planar driver to get a mostly great tuning.

Some comparisons

Compared with some of my other favourite Kiwi Ears IEMs clearly demonstrate how each model carves out its own sonic niche:

Drilling into each comparison:

The Astral has more sub-bass, while the Aether has a slightly warmer mid-bass and a more midrange focus to match that mid-bass:

Then the excellent Septet, the Septet is more V-shaped with deeper sub-bass and more elevated treble:

The now legendary KE4 with its New Meta tuning approach, I highlight 2 aspects:

1. KE4 has more sub-bass (actually a little but too much for my personal tastes, but I know lots of people love it)
2. Aether is more midrange vocal forward than a typical JM-1 focused tuning like the KE-4
3. Aether has more elevated treble, but mid-treble and in the upper treble regions

And finally with one of my all-time favourite IEM’s the more midrange focused Orchestra Lite:

1. Orchestra Lite has a more classic ‘headphone-like’ bass rolloff (almost HD600 like) and less mid-bass
2. But they both have that midrange forward tuning that I like.

I think this last comparison is the most interesting, as many people liked the Orchestra Lite but wanted more bass.

Distortion

The distortion performance at normal listening levels is excellent:

And as a percentage it is also excellent:

Even at louder levels, the distortion characteristics remain well-controlled:

The measurements confirm what the listening experience reveals: a well-tuned planar driver implementation that balances warmth with technical capability. The FR comparisons with other Kiwi Ears models clearly show the Aether’s is generall a more relaxed sub-bass, a more pronounced warm mid-bass, slightly forward vocal region, and a mostly smooth treble extension but with airy characteristics that distinguish it from its siblings.

Rating

The Aether earns a solid 4-star rating as another excellent IEM from Kiwi Ears. The single planar driver delivers a unique and engaging sound signature that stands apart from the brand’s other offerings. The excellent treble detail combined with the lovely subtly warm mid-bass creates a compelling listening experience.

However, I found the comfort and fit to be slightly less secure than some other recent Kiwi Ears models, with the IEM shell being more prone to becoming loose during extended sessions. This prevents it from achieving the perfect rating that some of its siblings have earned.

Who Should Consider the Aether:

• Listeners seeking a warmer, more relaxed planar driver experience
• Those who appreciate excellent treble detail without harshness
• Fans of the Kiwi Ears approach to distinct sound signatures
• Anyone looking for a single-driver IEM with coherent presentation

Conclusion

The Kiwi Ears Aether lives up to its name in more ways than one – the ethereal moniker perfectly captures the airy, spacious quality that defines this IEM’s character. The single planar driver successfully demonstrates how thoughtful tuning can create a distinctive and enjoyable sound signature that feels both grounded and otherworldly.

The name “Aether” suggests lightness and airiness, and that’s exactly what you get – a refined, delicate presentation with spaciousness that feels almost otherworldly in its execution, it is a solid recommendation for someone looking for a very nice planar IEM.