7Hz
7Hz Salnotes Zero:2
The Zero:2 is what happens when the internet's most influential IEM reviewer retunes an already-famous $20 earphone: it takes the original Salnotes Zero's near-neutral signature and adds a tasteful bass shelf, and the result is widely treated as the default answer to 'best IEM under $50.' Owners who own both this and the Moondrop Chu II consistently call the Zero:2 the cleaner, better-balanced listen — energetic low end, natural mids, and a treble that stays smooth without sounding dull. The 10mm dynamic driver with its PU-and-metal composite diaphragm keeps distortion impressively low, and the detachable 0.78mm 2-pin cable means the usual budget failure point is replaceable. At 32 ohms it's slightly less sensitive than some rivals but still runs fine from a phone or laptop. The honest caveats: the shells are lightweight colored plastic that looks toy-like next to metal rivals, the stock silver-plated cable is serviceable rather than nice, no case or extras beyond tips are included, and the short nozzles give some owners real trouble getting a seal — plan on tip-rolling if your canals are deep. Colorways are loud (the classic is a blue-and-white combo; this listing is orange). As a first IEM, a beater pair, or a reality check on how good $25 can sound, it has no serious weaknesses.
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Specifications
Highlights
Pros
- ✓Reference-grade 'neutral with bass boost' tuning rare at any price
- ✓Cleaner and more balanced than the Chu II per owners who have both
- ✓Low-distortion 10mm dynamic with PU+metal composite diaphragm
- ✓Detachable 0.78mm 2-pin cable, with 3.5mm or USB-C and mic options
- ✓Light, comfortable shells for long sessions
- ✓Runs adequately from any phone or laptop jack
Cons
- ✗Short nozzles make a good seal genuinely hard for some ears — tip-rolling likely
- ✗Plastic shells and basic cable look and feel their price
- ✗No carry case or accessories beyond ear tips
- ✗32-ohm impedance wants a touch more volume than sensitive rivals
- ✗Bright colorways aren't for everyone
Owner Insights(750 discussions)
The Zero:2 is the crowd-pleaser of the ultra-budget IEM duopoly. Where the original Salnotes Zero preached strict neutrality, the Zero:2 — tuned with input from reviewer Crinacle — adds a healthy scoop of warm sub-bass onto the same honest foundation, and owner discussions crowned it almost immediately: this is the $22 IEM for people who listen with their chest. For EDM, hip-hop, pop, and gym sessions it's the standing budget answer.
Daily use is simple: any dongle drives it, the angled shells lock in securely for most ears, and the included tip assortment sorts out fit. The compromises are visible and audible but forgivable at the price — thick plastic shells with a molding seam, a thin tangly cable, bass that's generous rather than fast, and treble tuned for safety over sparkle. The one genuine caution flag in long-term owner reports is reliability: a recurring minority describe a channel (frequently the right) failing within months, often resolved by rebuying rather than wrestling warranty shipping. At $22 that's an accepted risk; it's still worth knowing before recommending it as a gift.
Buy it if bass is your priority under $25 — its rival Moondrop Chu II counters with metal build, smaller shells, and slightly sweeter vocals, and the honest advice in every thread is 'Zero:2 for bass, Chu II for vocals.' Step-up money goes to the Truthear Hexa (~$85), which owners describe as the same philosophy executed with real resolution and control. There's no used market at this price — these are bought new, loved hard, and replaced without ceremony.
Pros
- +The bass upgrade the original Zero begged for — warm, thick sub- and mid-bass emphasis that makes it the budget pick for EDM, hip-hop, and gym use
- +Tuning shaped with reviewer Crinacle's input, so the boosted bass sits on an otherwise neutral, correct-sounding frame rather than a mud pile
- +Reigning co-champion of the $20-25 bracket — the default counter-recommendation to the Moondrop Chu II in every budget thread
- +Standard 2-pin detachable cable, and the revised cable is smoother with tighter connectors than the original Zero's
- +Secure, stable in-ear fit once tipped right; generous spread of colorful tip sizes in the box
- +Efficient enough for any phone dongle or console controller — no amp required, period
- +A mic-cable variant exists at the same price for calls and gaming
Cons
- −A pattern of owner reports describe one earpiece (often the right) dying within a few months even with careful use — the QC gamble is the model's known asterisk
- −Chunky 'marshmallow peep' plastic shells with a visible seam — bigger in the ear than the Chu II and unimpressive to look at
- −Larger shell overwhelms smaller ears; a fraction of owners can't get a comfortable seal at all
- −Bass speed and control are just okay — busy metal and fast basslines smear where the pricier Hexa stays composed
- −Stock cable is still thin and tangle-prone despite the revision
- −Treble is safe to a fault; detail-first listeners call the top end polite and unexciting
- −Warranty on a $22 Linsoul purchase is real but slow — dead-unit owners often just rebuy, which stings on principle
Common Questions
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