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We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
If you want two physically tuned, wired in-ear monitors with genuinely different sound signatures in one box, choose GAIT GlaXfi-eOne; if you need to turn your existing wired IEMs into true wireless with lossless Bluetooth and a powerful built-in DAC/amp, choose FiiO Link TWS(UTWS17.
• GAIT GlaXfi-eOne — biggest strength: one purchase, two tunings. A 25 μm glass diaphragm pair (White) for balanced, natural sound and a 50 μm flat glass diaphragm pair (Green) for punchy, bass-forward impact.
• GAIT GlaXfi-eOne — biggest trade-off: it's a fully wired, 3.5 mm analogue set. No Bluetooth, no app, no battery — your source device does all the work.
• FiiO Link TWS(UTWS17 — biggest strength: it converts MMCX or 0.78 mm 2-pin IEMs into true wireless, with Bluetooth 6.0, Snapdragon Sound, aptX Lossless/LDAC/LHDC V5, and a dedicated AK4333 DAC plus amp per channel.
• FiiO Link TWS(UTWS17 — biggest trade-off: it is not a headphone. It's an adapter, so you must already own compatible wired IEMs and accept app-based control and a recharge cycle.
• Who each pick is for: GlaXfi-eOne is for listeners who want two curated signatures and zero charging; UTWS17 is for IEM owners who want wireless freedom without giving up their favourite earphones.
The GlaXfi-eOne is unusual in a way that matters: it's a two-pack of in-ear monitors, each tuned differently on purpose. The White pair uses a 25 μm ultra-thin, 3D-formed glass diaphragm, and the design brief is clearly "resolution and balance" — deep soundstage, natural tonal weight, the fine detail of acoustic instruments rendered with a sense of air. The Green pair uses a thicker 50 μm flat glass diaphragm with high rigidity, and that tuning leans into tight, punchy bass with real physical impact.
That split is the whole point. Instead of buying one earphone and EQ-ing it, you get two physical tunings and pick the one that matches what you're playing. Jazz, classical and vocal-heavy tracks suit the White pair. Pop, hip-hop and rock suit the Green pair. I like that this forces a decision based on music rather than menus.
Physically it's a plastic, in-ear, wired design with a 16 ohm impedance and a 3.5 mm jack, weighing about 22.68 g. The 16 ohm figure is low, which means it will draw meaningful current from weak sources — a phone dongle will run it, but a modest portable amp or dongle DAC is the more natural partner. Noise control is passive sound isolation rather than active cancellation, and the lightweight build is aimed at long sessions without fatigue.
The bundle is generous: 6 pairs of S/M/L ear tips, a 3.5 mm-to-Type-C adapter, an airplane adapter, an oxygen-free copper cable, and a carrying pouch. There's a 30-day free returns and exchanges policy as the stated warranty description.
Who should buy it: listeners who want two contrasting reference-style signatures, who mostly listen at a desk, on a commute with a dongle, or on a plane, and who would rather not think about batteries. Who should skip it: anyone who wants wireless freedom, active noise cancellation, app EQ or a built-in amp. If your priority is cutting the cable, this isn't the product for you.
The UTWS17 solves a very specific problem: you love your wired IEMs, but you're tired of the cable. This is a true wireless Bluetooth adapter that plugs into MMCX or 0.78 mm 2-pin earphones and turns them into a wireless set. It runs on Qualcomm's QCC5181 platform with a quad-core architecture and dual Kalimba DSPs, supporting Bluetooth 6.0 and Snapdragon Sound for stable connections and low latency.
The wireless audio spec sheet is the headline. aptX Lossless, LDAC, LHDC V5 and aptX Adaptive are all supported, with transmission speeds up to 1.2 Mbps — that's the difference between "wireless is a compromise" and "wireless is close enough to CD-quality that I stop noticing." For anyone who has spent money on good IEMs, that matters more than any tuning gimmick.
Then there's the amplification. Each channel gets its own AK4333 DAC with integrated headphone amplification, delivering up to 85 mW + 85 mW at 32Ω. In plain terms: it can drive a wide range of IEMs, including harder-to-push ones, while keeping dynamic range intact and distortion low. It's effectively a tiny headphone amplifier hanging behind your ears.
The charging case is the practical upgrade — a built-in OLED display shows battery level, pairing status and charging details at a glance, and the interior is roomy enough for larger IEMs and ear hooks. Charge time is stated at 2 hours. Control is app-based, and there's no noise control at all — isolation comes entirely from whatever ear tips and IEMs you attach. It ships as a single item, weighs 0.4 kg, and carries a 1-year warranty.
Who should buy it: IEM owners with MMCX or 2-pin connectors who want wireless convenience, lossless codec support, and enough output to properly drive their existing earphones. Who should skip it: anyone without compatible wired IEMs, anyone who wants a self-contained product out of the box, and anyone who dislikes app-based control.
• Best for sound variety out of the box → GAIT GlaXfi-eOne. Two physical tunings (White balance, Green impact) beat one signature you have to EQ.
• Best for wireless freedom → FiiO Link TWS(UTWS17. Bluetooth 6.0 with Snapdragon Sound, aptX Lossless, LDAC and LHDC V5.
• Best for driving demanding IEMs → FiiO Link TWS(UTWS17. Dual AK4333 DACs with up to 85 mW + 85 mW @32Ω per channel.
• Best for zero charging and zero pairing → GAIT GlaXfi-eOne. A pure 3.5 mm wired connection with a 3.5 mm-to-Type-C adapter in the box.
• Best for frequent flyers → GAIT GlaXfi-eOne. An airplane adapter and a carrying pouch come included, and there's no battery to run flat mid-flight.
• Best for critical listening at a desk → GAIT GlaXfi-eOne. The 25 μm glass diaphragm pair is tuned for resolution, air and natural balance.
• Best for keeping the IEMs you already love → FiiO Link TWS(UTWS17. If your current earphones use MMCX or 0.78 mm 2-pin, this is the upgrade path.
• Best for low-latency gaming or video → FiiO Link TWS(UTWS17. Snapdragon Sound and aptX Adaptive target exactly that use case.
• Best for long-session comfort without battery anxiety → GAIT GlaXfi-eOne. Lightweight build, passive isolation, 22.68 g total.
In my opinion, these two products aren't really competitors — they're answers to different questions. If you want a complete listening solution you can unbox and use with anything that has a 3.5 mm jack or USB-C, I'd buy the GAIT GlaXfi-eOne. Two genuinely different glass-diaphragm tunings, a full accessory kit, and no charging to think about is a lot of listening flexibility in one box.
But if you already own good IEMs and the cable is the only thing annoying you, I'd buy the FiiO Link TWS(UTWS17. Bluetooth 6.0, aptX Lossless, LDAC, LHDC V5 and dual AK4333 DACs with 85 mW + 85 mW @32Ω is a serious wireless platform, and the OLED charging case makes it practical day to day. If I had to pick one for myself, I'd take the UTWS17 — but only because I already have IEMs I'd hate to abandon.
No. It's a wired in-ear monitor set with a 3.5 mm jack and a 16 ohm impedance. A 3.5 mm-to-Type-C adapter is included, but there's no Bluetooth and no battery.
No. It fits MMCX and 0.78 mm 2-pin connectors. If your IEMs use a different connector, this adapter won't attach without the right cable or adapter.
The GlaXfi-eOne relies on passive sound isolation from its design and ear tips. The UTWS17 has no noise control of its own — isolation depends entirely on the IEMs and tips you connect to it.
If you want to keep your current IEMs and go wireless, choose the UTWS17. If you'd rather have two tuned pairs, no charging and a compact travel kit, choose the GlaXfi-eOne. Either way, check the current price on Amazon before deciding — I don't quote prices here, and both are worth comparing at your budget.
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