By aspect — in detail
Tonality
Strong consensus · 9 srcThe most-agreed point in the whole field: measured against the common over-ear targets this sits unusually close, and listeners describe it as balanced rather than neutral — full, slightly warm of flat, with a deliberate lift low in the midrange.
“compliance to the target is the best of any open-back headphone that I have tested”
amirm, Audio Science Review
“The EXPANSE is not your typical neutrally tuned flagship headphone, but it is balanced in presentation, close to the Harman curve.”
Lieven, Headfonia
“Probably does not need EQ.”
Maiky76, Audio Science Review
Measured
Four rig readings across three labs agree on the shape: ASR's bench, Resolve's GRAS 43AG-7 (RA0402 ear sim, KB5000 pinna) and his Brüel & Kjær 5128, and Head-Fi HQ's own 5128 with an APx555. ASR's preference-score pass reads 76.1 unequalised and 90.4 with EQ — a gap small enough that Maiky76 concludes it does not need any.
Sources split, and the split has a known cause: Dan Clark dialled in a deliberate lift around 100–300 Hz, centred near 175 Hz. One camp hears that as drive and body; the other hears a mid-bass emphasis sitting over a sub-bass that stays polite by flagship standards.
Measured
The lift is documented from both directions. ASR was told before measuring that the company had dialled in a boost across roughly 100–300 Hz, and trialled a −2 to −3 dB correction; ASR's Maiky76 independently landed on a −3.64 dB filter at 136 Hz; and Dan Clark himself published the exact figure on Head-Fi: 'Per discussions on EQ points for Expanse to adjust tonality to be closer to STEALTH: PEQ 175Hz, Q=2.6, -2.5dB.'
⚠ vs. listeners — The graphs settle the quantity but not the preference, and the two camps are partly talking about different bands — the measured lift sits in the upper bass, while the 'not enough rumble' complaints are about sub-bass below it. Dan Clark adds a listening-level wrinkle: he notes that a listener who finds it bass-forward loud may find it just right quieter.
Where it splits
the lift is the point — it gives the headphone drive and weight67%
“Overall, I would say 70% of time of I preferred no EQ.”
amirm, Audio Science Review
quantity is modest — this is not a headphone you buy for rumble33%
“They will not achieve the kind of physical sub-bass rumble that a large dynamic driver can more easily.”
Eric D. Hieger, Home Theater HiFi
Most sources hear a forward but natural midrange, with a rise toward a peak around 3 kHz that keeps vocals clear. One high-authority dissent runs the other way — the reviewer whose own 5128 reads the mids as flat hears them as shouty.
Measured
Both sides are describing the same measured feature — a rise from the lower mids to a peak near 3 kHz, which Resolve's GRAS 43AG-7 and Headfonics' reading of the curve both identify.
⚠ vs. listeners — This is the clearest case on the headphone of a graph failing to predict a listener: Resolve's own 5128 shows a flat midrange and he hears shout anyway, which is why he expects 'a high degree of variation to how it’s perceived.'
Where it splits
forward and clear, but not shouty85%
“It also ensures the vocals stay clear, and relatively forward though not what I would term as shouty”
Marcus, Headfonics
the upper-mid emphasis reads as shout15%
“it measures reasonably flat throughout the mids, but I definitely hear this one differently (it sounds much more shouty to my ear)”
Resolve, Headphones.com forum
Sources split on whether the AMTS smoothness costs air. The larger camp hears extension without glare; a smaller one hears a dark top end missing its highest octave.
Measured
Nothing in the data reads as bright — the argument is about what is absent, not present. ASR flags a dip above 7–8 kHz but cautions that its measurements up there are not accurate; the two B&K 5128 rigs read that region more credibly and neither shows a hot treble.
⚠ vs. listeners — Above roughly 8 kHz the rigs cannot adjudicate, so the same slightly-under-target top end is reported as fatigue-free by most and as airless by a minority. The sharpest version comes from an owner who sold his pair: 'there’s no air, it’s a dark presentation for me without that missing upper treble that he picked up on immediately.'
Where it splits
smooth and extended — detail without glare77%
“it is not an overly spikey or hot treble response”
Marcus, Headfonics
Soundstage
Contested · 9 srcThe most divided aspect, and it splits three ways rather than two: genuinely enveloping, big-but-not-the-widest, or oddly flat and left-centre-right. The dissenters and the enthusiasts are describing the same headphone.
Measured
No rig measures stage, but there is a physical variable in play: the pads are unusually roomy inside and Resolve reports that where your ear sits changes the sound noticeably — which is why Dan Clark Audio puts written positioning instructions in the box.
⚠ vs. listeners — The split tracks head and ear geometry more than taste. Resolve, who measures for a living, puts it down to his own fit rather than a fault: 'this is potentially all just down to a unique HRTF situation that doesn’t work for me, where it will work for others.'
Where it splits
lives up to the name — large, enveloping, layered49%
“As the name implies, the soundstage is large and open, without sounding artificially distant.”
Eric D. Hieger, Home Theater HiFi
wide and deep, but not the widest open-back at this price28%
“I would not class the EXPANSE as spacious sounding as an HD800 or the Susvara”
Marcus, Headfonics
flat and left-centre-right — short on lateral definition23%
“to my ear I find it a bit lacking in lateral definition”
Resolve, Headphones.com forum
Imaging
Strong consensus · 5 srcBroadly praised as precise and three-dimensional, with instruments given real size rather than pinpoint dots. The exception is the same minority who hear a flat stage — for them the imaging goes with it.
“Imaging is distinct, and layering is phenomenal, especially with music that has a lot of space and separation.”
Eric D. Hieger, Home Theater HiFi
“What I absolutely love is the positioning, 3-dimensinonality, stereo imaging.”
Lieven, Headfonia
“I am really struggling with the soundstage sounding very L/C/R and not having very good imaging.”
ra990, Headphones.com forum
Detail
Strong consensus · 8 srcThe single strongest agreement in the set. Every source that discusses resolution rates it at or near the top of the class, and several reach for electrostatics as the comparison.
“Low level detail was stunning at times in the way they would stand out with superb clarity.”
amirm, Audio Science Review
“The Expanse is a very detailed headphone, and there's a crispness and snappiness to the sound that I equate with e-stats.”
Sara Schweiger, Moon Audio
“Unprecedented details and resolution (really!)”
gadus, Head-Fi owner review
Measured
ASR measured distortion low enough that it ran into the analyser's own noise floor — a SINAD of 86 dB that amirm attributes to the measurement rig rather than the headphone, calling the transducer basically distortion-less.
Rated well but conditionally: nearly every source ties dynamics to the amplifier, and the 'lacks slam' reputation that follows this headphone around is usually reported by people who later changed amps.
“When the EXPANSE are underpowered, the overall sound is blunted and disappointing.”
Eric D. Hieger, Home Theater HiFi
“EXPANSE’s dynamics are good, but they do strongly depend on the amp you’re using it with”
Lieven, Headfonia
“I would disagree with a common assessment that the Expanse lacks dynamics – I think they’re plenty dynamic”
Murphity, Head-Fi owner review
Comfort
Strong consensus · 8 srcEffectively unanimous, and one of the reasons the headphone keeps its owners. 418 g with a self-adjusting suspension strap, light clamp and deep pads; the only recurring caveat is that tall ears can brush the AMTS structure inside the cup.
“It is very comfortable to wear, nicely molding to my head.”
amirm, Audio Science Review
“they make the EXPANSE probably the best full-sized headphone on the planet for what comfort is concerned”
Lieven, Headfonia
“it’s right up there with the likes of the Meze Elite and Empyrean as some of the most comfortable headphones out there”
Marcus, Headfonics
Build
Strong consensus · 8 srcThe chassis draws unqualified praise — titanium headband, carbon-fibre baffle, folding gimbals into a small hard case. The cable and the box contents are where sources disagree, sometimes flatly: one reviewer records zero microphonics, an owner calls the same cable heavy and microphonic.
“They simply make the best built headphones in the industry, across the entire price range from the $500 Aeon RT to the $4k flagships.”
Murphity, Head-Fi owner review
“Exceptional build quality.”
Eric D. Hieger, Home Theater HiFi
“The cable is quite mediocre. It's heavy, microphonic, slightly stiff, and drags on the headphones as a result.”
Murphity, Head-Fi owner review
Isolation
Strong consensus · 4 srcUnusual for an open-back, and several sources raise it unprompted: it attenuates more incoming noise and leaks less than most open flagships. It is still an open headphone — people near you will hear it.
“The EXPANSE isolates better than your average open back with an unexpected degree of attenuation on background noise.”
Marcus, Headfonics
“Isolation-wise the EXPANSE for an open headphone doesn’t leak a lot of sound”
Lieven, Headfonia
“For open-back headphones, the isolation is good. Note: anyone nearby will take issue with that assertion.”
Eric D. Hieger, Home Theater HiFi
Genuinely argued, and the argument is three-sided: the engineering earns the price, the price is steep and the amplifier bill lands on top of it, or no headphone is worth this regardless of how it measures.
Where it splits
the engineering earns it — nothing else does this54%
“But this is the price right now for this unique offering in open back planar magnetic headphones.”
amirm, Audio Science Review
expensive, and the amplifier bill lands on top34%
“you will need to allocate more budget than normal headphones into the chain”
cpu235, Head-Fi owner review
no headphone justifies this, however it measures12%
“4 grand for a headphone is laughable regardless of how it measures. there is nothing in materials that justifies this cost!”
peanuts2, Audio Science Review forum
