Sonic Compass · Mojo Review · Earbuds · Session Review
FiiO UTWS17 (Link TWS)
FiiO's flagship Bluetooth ear hooks for detachable-cable IEMs. Across four IEMs I could not pick them from a wired DAP, with a silent background, natural timbre and a wide stage.
Wireless ear hooks that, by ear and across four IEMs, sounded as I remember the same IEMs wired, with a silent background. Watch the left-hook battery on my pair and the fit of some IEMs.
- Silent background
- Matched his wired IEMs by ear
- Natural timbre
- Wide, holographic stage
- Working 10-band parametric EQ
Where it sits
Sonic Compass does not score gear out of ten. Gear and listeners are plotted on the same seven axes, so a review tells you where a product sits — and you can see how far that is from where you sit. A position is a description, not a grade.
- Tone ColourBalanced · 52%
- Texture DetailVery detailed · 85%
- Dynamics JumpPunchy · 74%
- Space & ImagingVery spacious · 84%
- Timing & FlowBalanced · 55%
- Comfort & FatigueEasy-going · 72%
- Emotional EngagementImmersive · 78%
Neutral to natural. IEMs sounded as remembered wired, with natural timbre and rich vocals. No colour added that he names (high = warm on this scale).
Detail and subtle nuance intact on every IEM, micro details intact on the Luxear, and every click and strum audible on the second Tangzu.
Punchy, dynamic, full bass and quick, snappy transients on the Softears. He could not say whether it matches a balanced desktop amp.
Staging far and wide, 3D and holographic on the Luxear; very good stage and excellent imaging on the second Tangzu.
Placed neutral with little evidence. Quick transients and a frenetic metal track handled without trouble; no direct comment on timing.
Perfect fit first time, no sibilance and no mud at loud volumes, silent background. Held back by one Softears earpiece coming loose and a fast-draining left hook.
Was blown away and apologised to the maker for his doubts; sound felt full of life on the Luxear.
Sonic Compass does not grade gear. We plot gear and listeners on the same seven axes, so a review tells you where a product sits and you can see how far that is from where you sit.
The FiiO UTWS17, also sold as the Link TWS, is a pair of true wireless ear hooks that turn a wired IEM into a Bluetooth one. The pair was sent by FiiO for review. I came to it sceptical: I listen to IEMs wired, through DACs and a DAP, and Bluetooth was always a no for me.
I paired them with four IEMs I had reviewed before and compared against a cable and DAP from memory, so everything below is by ear only, on one phone (a Samsung Z Fold 7 using aptX).
Listening journey
Across four IEMs — I used a Softears IEM, two Tangzu IEMs (one of them budget) and a Luxear IEM, which I rate among the best I have heard. On every one, the sound matched what I remembered from my wired reviews. Bass stayed punchy and full, detail and subtle nuance were there, and timbre stayed natural.
Softears — Bass is punchy, dynamic and full. Transients are quick and snappy and note weight is as I remember it wired. Vocals are forward and rich with natural timbre.
Tangzu (budget pair) — Sounded as I remember it wired. Bass is low, and detail and resolution are full, with no subtle nuance missing.
Tangzu (second pair) — Magnificent. Detail is there in spades, timbre is natural and real. Staging is very good and imaging excellent, with guitars natural and rich, and I could hear every click, mouth movement and strum.
Luxear — Resolution is sewn up and the stage is far and wide, 3D and holographic. On a frenetic metal track I heard no loss in sound quality, with micro details intact and magnificent imaging. I was listening loud and heard no sibilance and no mud.
Versus a cable and DAP — I switched to a cable and DAP with 15 to 30 seconds between listens and could not remember a difference. I expect a cable and DAP to sound better, but not by a great deal.
Critical observations
Where the UTWS17 sits — It added nothing I could name to the IEMs: no colour, no loss. Strongest points are a dead silent background, natural timbre, and stage and imaging. I tried the EQ briefly and left it off.
Noise floor — Silent background even with sensitive balanced armature and hybrid IEMs. I heard no hiss.
Power — This is a wireless adapter for IEMs, not a desktop amp. I did not test planar IEMs and would not expect them to be a good match.
Features — Contactless wireless charging of the hooks, and a charging case with a display showing the battery of each hook. The FiiO app has a working 10-band parametric EQ with presets, and shows battery per hook. The app is easy to navigate and a joy to look at. Maker figures: Qualcomm QCC5181, Bluetooth 6.0, aptX Lossless, LDAC, LHDC V5, aptX Adaptive, AAC and SBC, with a dual AK4333 DAC (one per side) and about 8 g per hook.
Fit and handling — I had never used ear hooks and they fitted perfectly straight away. Connection to the IEMs was excellent. One Softears earpiece kept coming loose, and that was the only IEM that did.
Bluetooth — They failed to connect a couple of times, but once connected they stayed connected and never dropped out. In the app, leaving a screen takes you back to the My Device page, which is a minor gripe.
Battery — The left hook drained much faster on my pair. After a few hours it was at 6% while the right was at 86%. It could be just my pair, and I will follow up with FiiO. I did not give a total battery life.
Against the older model — I have not tried the UTWS5. From my research, if you own the 2025 UTWS5 and your phone does not do aptX Lossless, you can probably hold on to it. If you want the silent background, 10-band PEQ and the highest wireless bit rate, I see the UTWS17 as a no-brainer upgrade, or a solid first purchase.
Read this against your own profile — I prefer wired listening and have a cable and DAP. These changed my mind about Bluetooth for IEMs. If you want to cut the cord on IEMs with detachable cables, this fits.
Honest limits — The pair was supplied by the maker. By ear only, no measurements, one phone, aptX not aptX Lossless. The wired comparison is from memory over 15 to 30 seconds, not a level-matched blind test. I made no remark on timing or long-session comfort of sound, so those axes carry little evidence. I did not play with the side buttons or use the phone's calls.
Still to come — I plan to source 2-pin to 3.5 mm adapters and try these with headphones in a follow-up video.
- Driver Configuration
- True wireless Bluetooth ear hooks (adapter) for detachable-cable IEMs; Qualcomm QCC5181, Bluetooth 6.0
- Driver Details
- Dual AK4333 DAC and amp, one per side; up to 85mW per side at 32 ohms; aptX Lossless, LDAC, LHDC V5, aptX Adaptive, AAC, SBC (FiiO)
- Weight
- About 8 g per ear hook (FiiO)
- Build Materials
- Ear hooks with silver-plated monocrystalline copper wiring, IPX4 water resistance (FiiO)
- Cable Connectors
- Swappable MMCX and 0.78mm 2-pin connectors, both included (FiiO)
- Isolation Leakage
- Not applicable
- Power Requirements
- Rechargeable; contactless wireless charging of the hooks in the case, Type-C input (FiiO)
- Accessories
- Ear hooks, charging case with display, 0.78mm 2-pin connectors, Type-C USB cable, quick start guide, instruction card, warranty card (FiiO)
- Build Quality Notes
- Price: US$249.99 (HiFiGo listing; FiiO's own page gives no price). 10-band PEQ and settings via the FiiO Control app. Photos: FiiO via HiFiGo.
Wireless ear hooks that, by ear and across four IEMs, sounded as I remember the same IEMs wired, with a silent background. Watch the left-hook battery on my pair and the fit of some IEMs.
<p><strong>Buy it if</strong>… you own IEMs with detachable cables and want to cut the cord without losing the sound you know; you want a silent background with sensitive IEMs; or you want working parametric EQ and the highest wireless bit rates.</p><p><strong>Skip it if</strong>… you already own the 2025 UTWS5 and your phone does not support aptX Lossless; you plan to drive hard-to-drive planar IEMs; or you are happy with a cable and DAP.</p>