Sound Impressions
I’ve been using Astru for almost a month at this stage, and honestly, it’s been one of the most straightforward ‘testing’ experiences I’ve had to date. From the easy fit to the easy sound, this an IEM that nestles comfortably in your ears and plays everything you throw at it with a sweetness that belies its actual complexity.
Using a variety of my usual test tracks, several of which I’ve mentioned inline below, I’ve also been using Astru for music discovery over these past few weeks. It’s one of those IEMs I’d instinctively reach for every day, whether I’m popping out for a walk or sitting on the couch to peruse the latest album releases with Tidal.
I find Astru fairly source agnostic – I’ve been using Lotoo’s stylish PAW GT2 and its excellent Bluetooth DAC for a few days now, seeing how Astru isn’t an IEM that’s going to spotlight any issues with the obvious compression artefacts in a Bluetooth chain. But Astru is as much at home with an Apple dongle as it is with top-tier DAPs like GT2 and HiBy’s formidable RS8 II, and should sound close to optimal regardless of source.
Tonality
Astru presents with a mature, balanced signature with a gentle W-shaped curve that favours musical coherence over analytical dissection. It has the sort of tuning that doesn’t announce itself with exaggerated frequency spikes or bass shelf boosts, but rather settles into a natural presentation that lets the music breathe and flow.
One of the first things you might notice about the sound is its bouncy, juicy bass. There’s a distinct ‘thump’ in the low-end which, while not overly exaggerated, has that clean heftiness to it that you’d normally only find in a good dynamic driver. Combined with the metal shells, you’re going to feel the kick of drums and the rumble of the subs in any track that has them.
On Lana Del Rey’s Venice Bitch, the sub-bass extension is genuinely impressive (and that’s coming from a self-proclaimed basshead); there’s proper weight and rumble beneath the hazy production without overwhelming the midrange or muddying the mix. The bass response feels measured rather than indulgent, which means it doesn’t call attention to itself on sparse acoustic material but delivers satisfying impact when the track really demands it.
Is it the same rippled, textured bass you’d find in a pricier multi-driver dynamic bass setup? No, but it’s effortless in its naturalness, with a timbral accuracy that most non-dynamic drivers simply can’t replicate.
Astru’s midrange strikes a careful balance between warmth and clarity. Upper midrange is raised slightly above the fundamentals, encapsulating female vocals perfectly without shout, but also giving the sound a slightly harder edge on complex tracks.
Brandi Carlile’s vocals on The Joke sit naturally in the mix, neither pushed forward nor recessed into the background. There’s enough body to make voices feel human and present, but Astru avoids the thick, syrupy quality that can make some warmer-tuned IEMs sound congested.
Female vocals, as mentioned earlier, benefit mostly from this approach: Lorde’s higher register on Green Light, for example, comes through with energy and presence while avoiding the thin, shouty quality that plagues IEMs with aggressive upper midrange peaks.
If there’s going to be an Achilles’ Heel in a single-driver design, it’s more than likely going to be treble. While there’s definitely some energy in Astru’s treble, I find its upper-register extension mostly smooth and well-controlled.
Astru delivers just about enough air and sparkle to keep cymbals and hi-hats sounding crisp and detailed without tipping into brightness or sibilance, but not quite enough to space out the stage on more complex tracks.
There’s still some sense of openness in the upper registers that suggests the driver is genuinely extending well rather than simply rolling off, but Meze has wisely avoided the temptation to over-boost treble energy for the sake of perceived detail (I’m looking at you, Sennheiser). The result is a presentation that feels refined rather than aggressive, musical rather than analytical.
For less aggressive music, like the Eagles’ Hotel California, the acoustic guitar strings have proper shimmer and decay, and Don Henley’s vocals remain smooth and fatigue-free even during extended listening. I’ve tried eking out sibilance from some of my harsher test tracks, like Missy Higgins’ Shark Fin Blues, without much luck so far.
Overall, Astru’s is what I call a ‘Goldilocks’ sound: not too warm, not too cold; not too thin or thick. Just right. There’s some thump to keep things grooving, enough sparkle and clarity, a natural voicing through the midrange, and all considered, a sound that sits neatly in the pocket of what you’d expect when spending almost a thousand dollars on a premium acoustic instrument.
Technical performance
For a single dynamic driver, Astru hits all the right notes when it comes to technical ability too.
Imaging is precise without feeling artificially etched, and the soundstage has convincing width and decent depth without being the widest or deepest.
On Dire Straits’ Money for Nothing, the layered production separates cleanly; Mark Knopfler’s guitar sits distinctly to the left, vocals anchor the centre, and backing elements occupy their own space in the mix without collapsing into each other. It’s not the holographic presentation you might get from a well-tuned multi-driver setup (see my select comparison notes below), but it’s thoroughly convincing for a single-driver design.
Speed and dynamics are genuine strengths here. The gold-layered diaphragm delivers on its promise of fast transient response; percussion hits with proper snap and decay, and Astru handles complex, busy passages without too much smearing or compression.
Beyries’ Outer Reaches showcases this nicely: the delicate fingerpicking maintains its texture and articulation, while the subtle percussion in the background remains distinct and properly weighted. There’s a sense of effortlessness to the presentation that suggests the driver isn’t being pushed beyond its capabilities.
Resolution is where the single-driver approach shows its limitations compared to flagship-tier multi-driver designs, but only if you’re actively hunting for micro-detail. Astru retrieves plenty of information from well-recorded material; you can hear the resonance of Lana Del Rey’s vocal booth, the subtle string resonances on acoustic tracks, the ambient decay in live recordings.
What it doesn’t do is artificially highlight or exaggerate these details in a way that might impress initially but becomes fatiguing over time. The presentation feels organic and natural, which is precisely what Meze seems to be aiming for with this design – and all of its designs, really.
Select comparisons
Astru vs Sennheiser IE900 ($1,299)
To be fair, I haven’t had my previous-favourite single driver dynamic for a while, but I’m intimately familiar with its sound, having owned it twice and for extended periods each time.
IE900 takes a noticeably different approach to tuning, particularly in the low end and upper frequencies. Sennheiser dialled in more sub-bass presence compared to Astru, which translates to greater physical impact and rumble on bass-heavy material.
If you’re listening to Beyoncé’s Formation, for instance, IE900 delivers an even more visceral thump and weight in the lower registers, making the production feel more immediate and dynamic. IE900’s is one of the best bass presentations of any IEM, single dynamic or otherwise, so that’s somewhat to be expected.
Astru, by contrast, presents a more ‘neutral’ bass response that feels slightly lighter and more controlled, less impressive on first listen, perhaps, but also less likely to overwhelm delicate acoustic material.
Where the differences become more pronounced is in the midrange and treble regions. IE900’s upper midrange and lower treble are considerably more energetic, which brings female vocals and lead instruments forward in the mix and adds dollops of extra sparkle and air to the presentation.
On Lorde’s Royals, this extra energy makes her voice cut through with greater immediacy and presence, and the hand claps and percussion feel crisper and more defined. The trade-off is a brighter overall character that can edge towards sibilance on poorly mastered recordings or with certain vocal pairings.
Astru’s smoother approach through these regions makes it the more forgiving and fatigue-free option for extended listening. The Eagles’ harmonies on Seven Bridges Road remain balanced and sweet on Astru without any harshness, while IE900 can make the same track feel slightly hot and edgy.
If you value a more relaxed, easy-going presentation that you can listen to for hours without fatigue, Astru is likely the better choice. If you prefer more immediate treble sparkle and vocal presence, even at the cost of some smoothness, IE900’s tuning might appeal more.
Astru vs 64 Audio U12t ($1,999)
U12t represents a more reference-minded approach to IEM tuning, and the differences are immediately apparent.
64 Audio has nailed the upper midrange curve, making for some of the most realistic female vocal delivery on the market (yes, still). On Brandi Carlile’s The Story, U12t makes her voice feel almost intimately close, with every nuance and breath articulated clearly in the mix.
Astru presents the same track with more space around the vocal, placing it slightly further back in a more neutral acoustic perspective. Neither approach is inherently right or wrong, but they deliver fundamentally different listening experiences.
U12t’s treble region is also more elevated but somehow also less energetic, with an uptick in the air frequencies that creates a distinctly spacious and holographic stage for most recordings. This translates to enhanced detail retrieval and a greater sense of space and air in the presentation.
Dire Straits’ Telegraph Road benefits from this on U12t – the cymbals shimmer with more obvious extension, and the ambient hall information feels more present and explicit. Astru renders the same track with more intense treble, but not so much that it risks fatigue or brightness.
The bass response between the two is another clear differentiator. U12t dials in slightly more sub-bass presence, which gives it a touch more body in the lower registers, but it can’t quite deliver the same physicality and weight as Astru’s dynamic driver.
On Lana Del Rey’s Video Games, U12t’s bass feels more present and sustained, adding to the melancholic, dreamy atmosphere of the production. Astru’s bass response makes the same track feel ever-so-slightly lighter and more transparent, which some might find less emotionally engaging while others will appreciate the additional clarity, even though the distinctive sub-bass drops are more physical and textured with Astru.
Zooming out to the big picture of these three IEMs, Astru positions itself between the other two approaches: more forgiving and balanced than IE900’s bright, energetic signature, and more relaxed and musical than U12t’s reference-tuned, detail-focused presentation.
If you prioritise maximum detail retrieval and need a more refined, holographic and dare I say slightly analytical presentation, U12t is it (over most IEMs, actually). If you want maximum treble sparkle and immediate impact with single-driver cohesion, IE900 is where it’s at.
But if you’re after long-term listenability and tonal balance across diverse musical genres, Astru makes a compelling case, and probably pips the Sennheiser as my number one single dynamic driver pick (at least among those that cost less than a used car).
Closing thoughts
At £819/$899/€899, Astru positions itself as a serious high-end offering that stops short of the truly stratospheric pricing some flagship IEMs now command. It’s clear Meze has focused on making Astru a complete, ready-to-use system rather than expecting immediate cable upgrades or accessory purchases.
What strikes me most, having lived with Astru for weeks now, is how deliberately unhurried it feels in a market that rewards the loud, the extreme, and the gratuitously complex. It doesn’t try to dazzle you with a hyper-resolving treble shelf, nor does it flatter with an inflated bass shelf designed to impress on a thirty-second demo. It earns your attention over time, and that slow burn is exactly what makes it special.
Astru is an IEM built squarely for the long-haul listener – someone who values a coherent, balanced presentation across a broad range of genres over the thrill of a single frequency region done spectacularly.
It’s the right pick for those who listen for hours rather than minutes, who prioritise tonal naturalness and fatigue-free musicality, and who’d rather have a beautifully finished, ergonomically refined shell that disappears into the ear than a chunky statement piece that reminds you it’s there every thirty minutes.
That said, Astru won’t satisfy everyone. If you’re someone who prioritises micro-detail retrieval and the kind of holographic, near-out-of-head staging that flagship multi-driver designs can conjure, Astru’s single dynamic driver will feel like a polite step back. Those with cavernous ear canals may also find the smaller shell geometry a frustrating fit without an aftermarket tip selection.
I’d say that if your musical diet skews toward EDM or hip-hop where chest-punching sub-bass is the primary currency, there are more viscerally exciting options at this price point. Astru doesn’t deal in drama – and for some, that’s a dealbreaker.
For everyone else, this is Meze doing what Meze does best: delivering a product that’s as resolved in its aesthetic convictions as it is in its acoustic ones. Astru stands as one of the finest contemporary examples of single dynamic driver unity – a rare convergence of sound and shape that feels genuinely purposeful rather than merely assembled. Highly recommended.
Meze Astru is available now from major online retailers and direct from Meze Audio.
