We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
Updated: 2026-10-02 · 8 min read · Independent comparison
If you want a cable-free, open-ear design you can wear for hours while staying aware of traffic, coworkers and the world around you, choose Anker Soundcore V20i; if you need a wired, in-ear HiFi listen with a 3.5mm plug and a proper in-ear seal, choose TANCHJIM Zero Ultima. These two are not really rivals — they solve opposite problems.
• Anker Soundcore V20i's biggest strength: an open-ear hook design with four adjustable positions, touch controls, Bluetooth 5.4 multipoint and up to 36 hours of total playtime with the case.
• Anker Soundcore V20i's biggest trade-off: it is fully wireless with no 3.5mm jack, and the open-ear fit means it does not seal your ear canal — so it will not give you the isolated, in-head sound an in-ear monitor delivers.
• TANCHJIM Zero Ultima's biggest strength: a wired, in-ear dynamic-driver design tuned for detail, with a 10–48 kHz frequency range, a low-distortion dual-chamber acoustic structure and a lightweight 2.3 g-per-earpiece build.
• TANCHJIM Zero Ultima's biggest trade-off: it is a wired 3.5mm earphone with push-button controls and no Bluetooth — so no cable-free freedom and no charging case convenience.
• Who Anker Soundcore V20i is for: commuters, walkers, runners, office workers and anyone who wants all-day comfort and situational awareness.
• Who TANCHJIM Zero Ultima is for: listeners who want a wired in-ear monitor for music, gaming and calls, and who care more about sound detail than wireless freedom.
The V20i is a true-wireless open-ear earbud built around the idea that your ears should never feel plugged. The ear-hook shape sits outside the canal, and Anker gives you four adjustable positions so you can rotate the hook to the spot that feels most stable on your particular ear. That is the whole pitch in one sentence: comfort and stability without intrusion.
Under the hood, it runs Bluetooth 5.4 with multipoint, so you can stay connected to more than one device and switch between them. The drivers are 16mm dynamic units with titanium-coated domes and Anker's BassUp tuning, so despite the open design it is clearly aiming for a fuller low end than you would expect from something that does not seal. Four microphones plus AI processing handle calls. Touch controls sit on the earbuds themselves. There is even a tune-synced lighting feature if you like your audio with a visual flourish.
Battery is where it gets genuinely practical. Anker rates the buds at around 8 hours per charge, with the case pushing total playtime to roughly 36 hours. Recharging the buds takes about 1.5 hours, and the case itself takes around 2.5 hours from a 700 mAh cell. The whole set weighs 76.4 g, and the case alone is 57.8 g — light enough to live in a jacket pocket. It carries an IP55 rating, which covers dust and water spray, and it comes with an 18-month warranty.
Who should buy it? Anyone who spends the day in noisy-but-social environments: cycling to work, walking the dog, taking calls while cooking, sitting in an open-plan office where you still need to hear your name called. The open-ear format is the point — it keeps you aware rather than sealed off. Who should skip it? If you want maximum isolation, deep bass slam, or a wired connection with zero latency and zero charging, this is not the tool. It has no headphone jack and its noise control is listed as none.
The Zero Ultima is the opposite philosophy: a wired, in-ear earphone that puts a proper seal in your ear canal and feeds it a carefully tuned signal. TANCHJIM uses a proprietary dual-chamber single dynamic driver with a PET titanium-dome composite diaphragm and a labyrinth-style rear acoustic chamber. The headline engineering claim is harmonic distortion held below 0.05% at 94dB, which is the kind of number that tells you the brand is chasing clean, controlled output rather than just loudness. Frequency response is listed at 10–48 kHz, impedance at 30 ohm.
The tuning story is a balanced three-band presentation with strong mid-to-low frequency control, delicate vocals and deeper bass extension. This is the classic entry-level HiFi brief: give a first-time IEM buyer something that sounds noticeably more detailed than a bundled phone earbud, without demanding a dedicated player.
The physical design is deliberately minimal. Each earpiece weighs just 2.3 g with a slim 10.5 mm body, a scientifically angled nozzle and a deeper fit. TANCHJIM explicitly frames this as comfortable enough for side-sleeping — though the brand also sensibly recommends removing earphones before you actually sleep. The cable is a two-core oxygen-free copper wire with silver plating, low resistance and low capacitance, and it is built to resist tangling and untangle with a shake. The housing is copper and metal in a silver finish.
Connectivity is a 3.5mm plug — this specific version includes a microphone. Controls are physical push buttons, not touch. It is compatible with phones, laptops, tablets and the Switch. There is no Bluetooth and no noise control listed. The warranty runs one year. Who should buy it? Gamers who want low-latency wired audio and impact-heavy sound cues, listeners who want an affordable step into in-ear monitors, and anyone taking calls who wants a wired mic that will not drop out. Who should skip it? Anyone who refuses to deal with a cable, or who wants the freedom of a charging case and multipoint.
• Best for all-day comfort and situational awareness → Anker Soundcore V20i. The open-ear hook design and four adjustable positions are built exactly for long sessions where you still need to hear the room.
• Best for sound detail and in-ear isolation → TANCHJIM Zero Ultima. A sealed in-ear fit plus a low-distortion dynamic driver is the recipe for detail and bass extension.
• Best for battery life → Anker Soundcore V20i. Roughly 8 hours per charge and up to 36 hours total with the case, versus a wired earphone that draws no power at all but needs a device.
• Best for zero-latency gaming → TANCHJIM Zero Ultima. A wired 3.5mm connection sidesteps Bluetooth latency entirely, and TANCHJIM tunes for in-game impact sounds.
• Best for calls in a busy environment → TANCHJIM Zero Ultima. The omnidirectional mic on a wired connection is stable, and the in-ear seal blocks some surrounding noise.
• Best for workouts and weather → Anker Soundcore V20i. IP55 dust and spray resistance plus a secure hook fit is a better match for movement than a wired cable.
• Best for multi-device switching → Anker Soundcore V20i. Bluetooth 5.4 with multipoint lets you hop between devices without unplugging anything.
• Best for minimal weight in the ear → TANCHJIM Zero Ultima. At 2.3 g per earpiece, it is about as light as an in-ear gets.
In my opinion, I would buy the Anker Soundcore V20i if my day involves movement, calls and staying aware of my surroundings — it is the more versatile object, and the open-ear format plus multipoint plus 36-hour case life covers more real-life situations than a wired earphone can. I would buy the TANCHJIM Zero Ultima if my priority is pure listening: a sealed in-ear fit, a low-distortion dynamic driver and a wired connection for gaming and music detail. If you can only pick one and you listen critically more than you commute, go TANCHJIM. If you live in your earbuds all day, go Anker.
how to make wired earbuds stay in ear
Fit is the whole game. The Zero Ultima uses a deeper, angled nozzle and a rounded-tip shape to seat inside the canal, and it ships with a slim 10.5 mm body so it can sit further in without pressure. The practical fix for most wired buds is trying different tip sizes and gently twisting the earpiece as you insert it so the seal forms. A proper seal is also what gives you the bass and isolation a wired IEM is capable of.
how to put earbuds in your ear
For in-ear models like the Zero Ultima, pull the top of your ear slightly up and back, slide the nozzle in at the angle of your ear canal, then let go — the tip should expand and seal without you forcing it. For open-ear hooks like the V20i, the process is different: hang the hook over the back of your ear, then rotate between its four adjustable positions until the driver sits comfortably outside the canal and feels stable when you shake your head.
how to keep earbuds in ears
The Zero Ultima relies on a correct tip seal and its angled nozzle; if it keeps working loose, the tip is usually the wrong size. The V20i has a built-in advantage here, since the ear-hook design and four adjustable positions exist specifically to lock the bud in place. For any earbud, cleaning the tips and your ears of oil, and avoiding tugging the cable, both help keep the fit stable through the day.
how to make apple wired earbuds stay in ear
The same principles apply to any wired in-ear: match the tip to your canal, insert with a slight twist, and route the cable so it is not pulling downward on the earpiece. If your ear shape does not hold a rounded tip well, an over-ear hook or a different tip material is the usual workaround. The Zero Ultima's deeper, angled fit is designed to reduce exactly this kind of slipping compared with a shallow, one-size bud.
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