In-Ear MonitorOverreview

7Hz Salnotes Zero

The $20 set that made cheap IEMs serious — still adored by the measurement crowd, still too hot up top for a growing share of its critics.

37 sourcesUpdated
$21Typical US price

Score aggregates reviewer opinions across topics.

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7Hz Salnotes Zero

The short version

What to know.

The 7Hz Salnotes Zero is a ~$21 single-dynamic-driver IEM from 2022 that sits close to the Harman in-ear target through the midrange, and one of the most divisive sets in the budget bracket. Most reviewers agree the midrange is clean and vocal-forward, that detail and soundstage are respectable but average, and that it was outstanding value — a view the measurement-forum audience still holds. Almost everything else splits. The treble is the main argument, and the 'too hot' camp now carries more weight than the 'well-judged' one: critics describe fatigue, sibilance and a sharp upper-treble peak, while many owners hear nothing to fix. Measurements from 44 rigs explain both: the ear gain is normal, but above 12 kHz most rigs show energy well over target, and how much depends heavily on rig, insertion depth and tip. Reviewers also split on whether the light, sub-bass-only low end is enough, whether the tuning is truly neutral, on imaging, on the angular shell's comfort, on isolation (which tracks seal) and on build, where a channel slowly going quiet is the most common owner failure.

About this product

The original ~$20 Salnotes Zero (July 2022): a single 10 mm dynamic driver with a metal composite diaphragm and N52 magnet, in a plastic shell with a stainless-steel faceplate, on a detachable 0.78 mm 2-pin cable — sold without a mic (3.5 mm) or with a mic on a 3.5 mm or USB-C cable, now in six colours. Crinacle has said he tuned it but kept his name off it, so unlike the Zero:2 it carries no collaboration badge; a 'Mecha Edition' colourway measures essentially the same. Not the bassier 7Hz x Crinacle Zero:2, and not the separate Truthear x Crinacle Zero / Zero:RED / Zero:BLUE(2) or the Tanchjim Zero.

In July 2022 a roughly $20 earphone with a single 10 mm driver and, unusually for the price, a detachable cable turned up from 7Hz's budget sub-label Salnotes. The 7Hz Salnotes Zero became the set people pointed at to argue that the ultra-budget bracket had stopped being a compromise, and it kicked off the sub-$25 arms race that produced the Zero:2, the Simgot EW200, the Moondrop Chu II and a dozen others. It later emerged that Crinacle had tuned it and chosen to leave his name off the box.

Four years on it is still on sale, still about $21, and its reception still has not converged. Audio Science Review's readers vote it overwhelmingly 'Great' and most Head-Fi owners give it five stars, while the ranking lists kept by headphones.com's reviewers put it near the bottom of their tables. Both sides are describing the same earphone — and mostly arguing about what happens above 5 kHz.

A good fit for

  • Listeners who want midrange clarity and vocal presence above all else
  • Anyone who prefers a clean, un-warm low end over punch and weight
  • First IEM buyers on a strict ~$20 budget who want a detachable cable
  • People happy to EQ — owners often tame it with one narrow cut around 12–13 kHz
  • Listeners willing to experiment with tips, which change both its bass and its treble

Think twice if

  • You are treble-sensitive — the upper treble is the most common reason critics give up on it
  • You want bass weight or slam — the shelf is light and sub-bass only
  • You want a warm, thick or forgiving tone — the voicing is deliberately lean
  • Your ears dislike angular shells, or you need dependable isolation for noisy commutes
  • You want the current best budget set rather than the historically important one — the bracket it created has moved on, including 7Hz's own Zero:2

The reviewer consensus

Agreement &
disagreement.

7 / 12topics divide opinion
midsdetailsoundstagedynamicsvaluetreblebasstonalityimagingcomfortisolationbuild
5 Mostly agree7 Divided opinions

Common ground6

  • The midrange is the strong point — clean, transparent and vocal-forward, with no bass bleed.
  • Detail and soundstage are respectable for the money but average in absolute terms: clarity is real, micro-detail and space are not exceptional.
  • Transients are quick and tidy, but impact and note weight are on the light side.

Points of contention7

  • Treble: 'fatiguing, sibilant, with a punishing peak' vs 'smooth, airy, nothing to fix' — with the 12–14 kHz region, which fit and tips move a lot, at the centre.
  • Whether the bass is enough: the same clean sub-bass shelf reads as ample to one camp and subdued and below neutral to the other.
  • Whether it is neutral at all — from 'the same accurate, neutral response I like to hear' to 'thin and small sounding'.

A closer listen.

12 topics · 7 divided
Left: criticalRight: positiveTighter lines: more agreement

Treble

Leans criticalDivided opinions
Reviewer sentiment28 supporting sources
CriticalNeutralPositive

Band: opinion spread · Dot: weighted average

Sources split, and this is the argument that defines the set. The larger camp — the headphones.com ranking lists, Soundphile, SoundGuys, Headphonesty, several ASR members and Reddit owners — hears an upper end that turns fatiguing, sibilant or peaky, and names either the presence region or a sharp peak around 12–13 kHz. The other camp, including amirm and most Head-Fi reviewers, hears smooth, airy treble with nothing that needs fixing. The split tracks fit as much as taste: one rig's insertion series moves the top octave by eight decibels, and tip choice moves it by several.

Measured

Across 44 squig.link rigs (normalised at 500 Hz, against Harman IE 2019 on the same normalisation) the ear gain is not the problem: it peaks at a median 3.15 kHz and sits about 1.5 dB under target at 3 kHz. The Zero then runs about 3 dB under target at 5–6.5 kHz, about 2 dB over at 8 kHz, about 4 dB under at 10 kHz — and at 13 kHz a median 8 dB over target, with rigs ranging from −4.1 to +7.5 dB there. amirm measured a peak around 12.7 kHz but says his fixture is not accurate in that region. listener's coupler insertion series moves 13 kHz from +6.8 dB (shallow) to −1.7 dB (deepest) and 6.5 kHz from +8.2 to +1.0 dB; swapping to Azla or Spinfit CP100 tips cuts 13 kHz by about 4.7 dB.

vs. listeners — The rigs support both camps. Through 4 kHz the Zero is at or slightly under target, so complaints about the presence region are not about an oversized ear-gain peak; but most rigs do show a strong resonance in the 12–14 kHz region, which is where amirm, ASR members and Reddit owners aim their EQ cuts. That band is also the one couplers measure least reliably and the one insertion depth and tips move most — so whether the peak lands on a listener's ear depends on fit, which is the likeliest reason the verdicts are so far apart.

Where it splits
Too hot — fatiguing, sibilant or peaky up top, with a sharp upper-treble resonance many end up EQing out.58%

“Would be good if it didn't have the most punishing lower treble and length mode resonance issues.”

Resolve (headphones.com IEM ranking list)
Well-judged — smooth, airy and extended, with nothing that wants fixing.42%

“I could see someone liking it better that way but I liked it without.”

Audio Science Review (amirm)
Link to this topic

The hardware

Specifications.

Checked

Design

Type
In-ear monitor
Drivers
1 × 10 mm dynamic (metal composite diaphragm, N52 magnet)
Housing
plastic chassis with a stainless-steel faceplate

Electrical

Sensitivity
108 dB/V
Frequency response
10 Hz – 20 kHz

Connection

Cable
Detachable
Connector
0.78 mm 2-pin (not recessed)community-sourced: socket depth

Manufacturer-published figures, not measurements · from linsoul.com. Socket depth not published by the maker — community-sourced from hands-on reviews: primeaudio.org, head-fi.org.

Follow the evidence

Sources 37

1–6 of 37 sources

Read with context

Limitations & method.

As of

What to keep in mind 7

  1. This is a read of where the reviews land as of October 2026, on a set from 2022 — and the ultra-budget bracket it helped create has moved fast since, with the 7Hz Zero:2, Simgot EW200, Moondrop Chu II, Tangzu Wan'er and Truthear Gate all crowding the same shelf.

  2. Opinions on this one really are further apart than usual. The forum that measures gear rates it near-perfect while professional ranking lists put it near the bottom — read which kind a reviewer is before reading their verdict.

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