By aspect — in detail
The one genuinely contested axis. The measured facts are agreed: versus the original Zero the Zero:2 tames the old upper-treble peak and drops presence through roughly 4-8 kHz, so it's smoother, safer and less airy. Where reviewers split is on the verdict. One camp — most editorial reviewers and comfort-first listeners — calls it non-fatiguing and ear-friendly, a clear improvement on the OG's occasional harshness. A measurement-backed camp calls it too recessed/dark, short on sparkle, and best restored with a touch of EQ. A lone outlier (Headphonesty) still finds it can get shouty on busy tracks.
Measured
Both a GRAS 45CA (ASR) and a B&K 5128 (Resolve) read the same tilt: the original Zero's upper-treble peak is removed and there's a real dip through the 4-8 kHz region — amirm quantifies it as a '5+ dB' treble shortfall; Acho Reviews' squig.link work calls the 5-6 kHz dip 'a little too pronounced.' Upper-treble air rolls off, so sparkle is reduced. amirm's AB tests preferred a treble-lifting EQ.
⚠ vs. listeners — Same measured smoothing, opposite verdicts: what one camp hears as 'safe and non-fatiguing' the other measures as a 5 dB shortfall and hears as 'recessed/dark.' The two heaviest measurement sources land on the critical side — amirm preferred EQ, and Resolve's ranking-list note is bluntly 'Treble is still a problem' — while most subjective reviewers count the calmer top as an upgrade.
Where it splits
Smooth, laid-back and non-fatiguing — the OG Zero's harsh peak is gone; a comfort win that keeps enough clarity.55%
“This results in a more laid-back treble, stepping back from the limelight while still unravelling sufficient details.”
Prime Audio
Too recessed/dark and short on air — a real ~5 dB treble shortfall that measurement-minded listeners prefer to EQ back.45%
“the highs were a little recessed and at times I was hearing bass I didn't even know was there!”
Audio Science Review (amirm)
The headline change and the near-universal highlight: about +3 dB over the original gives real sub-bass rumble and a punchy, articulate mid-bass from the new 10 mm driver — powerful and fun without going full basshead. It's mostly praised as controlled, but the picture isn't unanimous: a few measurement-leaning reviewers hear a touch of mid-bass bloat, a basshead finds it doesn't hit hard enough, and one reviewer (Headphonesty) even calls it bass-light. RedditRecs flags the bass as 'polarizing,' and much of that tracks fit — a deep seal is needed to lock in the slam.
“With the 7Hz Zero 2, the bass takes centre stage, embodying a newfound depth and resonance.”
Prime Audio
“the sub-bass is the star and the mid-bass feels a bit bloated.”
Hi End Portable
Measured
The spec sheet adds ~3 dB in the low frequencies versus the original Zero; Resolve's 5128 graph shows 'noticeably more presence in the midbass area' where the OG ramped mainly into the sub-bass. Extension reaches down to ~20 Hz with a seal, and amirm's distortion measurements are exceptionally low even at high SPL, so the bass stays clean. Perceived quantity is strongly seal-/fit-dependent.
Tonality
Moderate · 13 srcBroad agreement on the recipe even as labels vary: a warm-neutral balance with boosted bass and a tamed treble — variously called warm-neutral, a mild V/W, U-shaped, or 'another Harman/DF with more bass.' The through-line is a deliberate, more consumer-friendly, fun-leaning move away from the original Zero's leaner, more reference tuning, and amirm confirms it still holds close to a sensible target. Whether that warm tilt suits you is the taste question behind the treble and 'is-it-an-upgrade' debates.
“A warm-neutral, bassy take on the Zero: a thick, satisfying low-end with tidy mids and a smooth, non-shouty top that trades sparkle for comfort.”
iemranking (review aggregate)
“7Hz Zero 2 has a warmer, more fun sound signature compared to the original Zero.”
Prime Audio
Measured
amirm reads it as 'excellent compliance with our target,' with a lift between ~100-300 Hz and a shortfall from ~4-8 kHz — i.e. warmer and smoother than neutral rather than a strict reference line. Specs: 10 mm dual-cavity DD (PU+Metal diaphragm), 32 Ω, 108 dB/V (93.1 dB/mW), 10 Hz-20 kHz.
Consistently rated a strength for the price: clean, natural and un-recessed, with a touch more body and warmth than the original thanks to the extra bass. Reviewers call the midrange linear and free of shout or sibilant peaks; vocals stay clear even if they're not the forward focus. The modest dissent is that the added warmth can thicken the presentation, and a couple of reviewers hear male vocals as slightly lean or short on texture and expression.
“The Zero: 2 have a very linear midrange.”
Headphonesty
“Vocals stay clean and fairly natural (not buried), but the extra bass can make the presentation feel a bit thicker than the OG Zero.”
iemranking (review aggregate)
Soundstage
Moderate · 9 srcA pleasant surprise for the money rather than an absolute strength. Reviewers converge on a stage that's average in size but well beyond expectations at $25 — not congested, with more depth than width and a mostly frontal presentation. A minority (and OG-Zero fans) hear the original as more open, tying the Zero:2's slightly closer stage to its heavier bass.
“the Zero 2 punches well above its weight class. The improved driver design and tuning seem to create a surprisingly spacious soundstage.”
Gears For Ears
“Stage is average with a presentation that can feel more depth than width”
iemranking (review aggregate)
A quiet, consistent strength: cohesive, tidy separation and solid positioning that reviewers and owners single out as good for the price — a set that sounds 'together' rather than pinpoint-analytical. It's also cited as a budget gaming pick for positional audio, with little real disagreement here.
“the Zero: 2 achieve very decent imaging.”
Headphonesty
“Also amazing is the level of instrument separation/spatial qualities. So, so satisfying.”
Audio Science Review (amirm)
The agreed technical limiter. Most reviewers land on 'average resolution' — honest, tonal detail rather than a treble trick, and generally a hair less resolving than the original because of the softer top. Several note it slightly trails the OG here; a couple (Hi End Portable, and amirm once EQ'd) think it resolves better than its price and graph suggest. Either way, detail retrieval is the thing the tuning-first Zero:2 gives up first.
“Not as resolving or detailed as the original”
Prime Audio
“rather more resolving than the price, profile and frequency response might lead one to believe.”
Hi End Portable
Measured
Micro-detail is capped by the rolled-off upper treble more than by any lower-frequency smearing; amirm found perceived detail ('the highs are to die for') improved noticeably with a treble-lifting EQ, which supports the read that resolution is limited by tuning, not driver competence.
Rated punchy and lively, driven by the enhanced low end — a set that slams and feels fun rather than flat or over-controlled. It won't feel ultra-fast on busy tracks against pricier sets, and the dynamism is bass-led, but for the class it's an engaging, energetic performer.
“the Zero 2 goes into party mode as the bass thumps and rumbles.”
Prime Audio
“punchy and dynamic in the bass”
iemranking (review aggregate)
A near-universal high point with one asterisk. The feather-light (~4 g) shells disappear in the ear and are widely called all-day comfortable. The asterisk is fit depth: the nozzles are fairly short and insertion is shallow, so a minority (including Resolve) can't get a locked-in seal, and RedditRecs lists both 'comfortable for long sessions' and 'uncomfortable fit for some ears.' Tip rolling and a deeper seal resolve it for most.
“the design is quite comfortable and you will be able to wear the IEM all day long without any discomfort.”
Gears For Ears
“It doesn't work for me personally, but that's in large part due to the more shallow fit.”
Resolve, Headphones.com
Adequate for $25, with recurring caveats. The translucent plastic shells look toy-ish but are sturdier than they appear, and the new colourways are an improvement. Opinions on the cable split — a couple of reviewers find the SPC cable softer/better than the OG's, but the dominant verdict is that it's cheap and thin, there's no case, and there are scattered reports of a channel failing. Accessories are basic (generous on tips, nothing else).
“Frankly, only airline freebie earbuds have dinkier cables.”
Headphonesty
“the right earbud of the Zero:2 actually started to die on me after a few months even with careful use.”
StreamTech Reviews
Isolation
Moderate · 6 srcAverage to good, and seal-dependent. It's a vented sealed design, so with a solid (ideally deep) fit and the right tips it isolates well enough for commuting and everyday use — some owners rate isolation as a standout — while a shallower fit gives only average passive attenuation.
“Passive noise isolation is average, making the Zero 2 suitable for most everyday environments.”
Prime Audio
“Isolation is typically average to good if you get a solid seal”
iemranking (review aggregate)
Value
Strong consensus · 13 srcThe broadest agreement of all: at ~$25 (often ~$20 street) the Zero:2 is treated as outstanding value and a safe blind-buy budget default — 'some of the best value in all of audio' in Resolve's words, #1 in IEMs by Reddit sentiment, and 4.2/5 across thousands of owner ratings. The honest counter is that it's an incremental sidegrade to the original rather than a leap, the accessories are basic, resolution is only average, and expert scores actually scatter widely (3.6 to 8.3 out of 10) — so 'great value' is nearly unanimous, but 'great set' depends on which camp you're in.
“But if they work for you this could be some of the best value in all of audio.”
Resolve, Headphones.com
“excellent value tuning with big, enjoyable bass and safe treble; it's mainly held back by average resolution and basic accessories”
iemranking (review aggregate)
Measured
$24.99 MSRP, frequently ~$20-22 street. Aggregates: 6.1/10 IEMR-normalized across 8 expert reviews (reviewer average 5.7, per-reviewer scores from 3.6 to 8.3) on iemranking; 77% positive across 502 aggregated Reddit reviews and #1 in IEMs on RedditRecs; 4.2/5 from 3,262 Amazon ratings and 4.2/5 from 22 Head-Fi ratings.
