FiiO LINK TWS Ear Hook Bluetooth Adapter for IEMs

The FiiO LINK TWS (UTWS17) gives your wired in-ear monitors the wings of wireless hi-fi. Each earhook has a flagship Qualcomm QCC5181 Bluetooth 6.0 chip and its own AKM AK4333 DAC and amplifier, delivering 85mW into 32Ω with a 111dB signal-to-noise ratio, and it supports aptX Lossless, LDAC, LHDC V5 and aptX Adaptive for CD-quality lossless wireless sound. Swappable MMCX and 0.78mm 2-pin connectors fit most detachable-cable IEMs, and the case charges the earhooks wirelessly, with no contacts to corrode, and shows their status on its display. Built on FiiO’s years of experience with true wireless amplifiers, it aims for wireless sound that rivals a wired connection.

A real hi-fi DAC/amp in each earhook

Rather than relying on the Bluetooth chip’s own audio output, each compact LINK TWS earhook contains a fully independent hi-fi DAC/amp: the QCC5181 receives the high-definition signal and passes it digitally to a 32-bit AKM AK4333, which decodes and amplifies it. The AK4333 is a high-performance, efficient chip with a built-in amplifier and AKM’s signature VELVET SOUND technology, optimised for true wireless use, for a rich and detailed sound.

The difference shows in FiiO’s measurements: the QCC5181’s maximum specs on its own are 105dB SNR, 0.004% distortion and 30mW into 32Ω up to 20kHz; FiiO’s earlier UTWS5 reached 109dB, 0.002% and 33mW; the LINK TWS reaches 111dB, 0.002% and 85mW, with a response to 40kHz.

Flagship QCC5181 Bluetooth

Qualcomm’s flagship QCC5181 brings Bluetooth 6.0 and a quad-core architecture with dual 240MHz Qualcomm Kalimba audio DSPs, giving ample computing power for complex decoding and multitasking with bit-perfect lossless audio. It supports Snapdragon Sound with compatible phones, for immersive, high-definition wireless audio, and has a range of about 10m.

Lossless, high-resolution codecs

The LINK TWS supports SBC, LC3, aptX, aptX Adaptive (96kHz/24-bit), aptX Lossless, LDAC and LHDC V5 (192kHz/24-bit). With lossless wireless bit rates of up to 1.2Mbps, it delivers true CD-quality lossless audio, restoring every nuance as if you were in the middle of the performance. Your phone needs to support a codec to use it; LHDC V5 in particular needs a compatible phone.

Low-latency game mode

Turn on game mode with a single tap and aptX Adaptive cuts latency to as low as 74.6ms, keeping sound in sync with the action so you can pinpoint opponents by ear. Game mode uses a little more power.

Clear calls

Each earhook has a dual-microphone array with an upgraded CVC noise-cancelling algorithm and 32kHz aptX Voice wideband audio, which filters out ambient noise and picks up your voice precisely, so you are heard clearly and naturally even in noisy places. A transparency mode lets you hear your surroundings.

Wireless charging and a case with a display

Instead of pogo-pin contacts, which can oxidise and collect dirt, the case charges the earhooks wirelessly, without contact, for better long-term durability. The earhooks switch off when you put them in the case, switch on when you take them out, and stop charging when full; they may feel slightly warm after charging, which is normal. The spacious case suits a wide variety of earphone shell sizes, and its OLED dot-matrix display shows pairing status and battery levels at a glance. The earhooks play for about 7 hours (SBC) or 5 hours (LDAC) per charge, the case recharges them twice for up to 20 hours in total, and both charge in up to 2 hours.

Light, comfortable and well made

Each earhook weighs only 8g, with an ergonomic shape and a skin-friendly, food-grade nano coating, so it is comfortable enough to almost disappear and stays put however active you are. Inside, silver-plated monocrystalline copper wiring carries the audio signal for excellent conductivity and resolution. Large, sensitive physical buttons respond to a light press for play/pause, volume and track skipping.

One pair of earhooks for MMCX and 2-pin

Swappable MMCX and 0.78mm 2-pin connectors come as standard, so one pair of earhooks works with both connector types, with no need to buy separate versions for different earphones. FiiO designed the case around earphones about the size of its FH19 (about 21.4 × 24.4mm and 21.4mm deep); as the space inside is irregular, this is only a guide.

IPX4 and app control

Waterproof membranes, water-resistant acoustic cotton, a seal ring and a detachable silicone ear-hook base give IPX4 resistance to sweat and splashes, verified in FiiO’s laboratory. In the FiiO Control app you can set the 10-band PEQ (and import, export and share curves), channel balance (12 steps each way, 0.5dB per step), multipoint connection and Hi-Fi or game mode, and update the firmware over the air. The output adapts to earphones from 8Ω to 100Ω.

Good to know

• Earphones are not included: you need IEMs with detachable MMCX or 0.78mm 2-pin cables. If you are not sure yours will fit, ask us before you buy.
• Codecs depend on your phone. There is no AAC, so iPhones connect using SBC; aptX Lossless, LDAC and LHDC V5 need an Android phone that supports them.
• IEMs to try it with: FiiO’s FH3 (MMCX). See also the FiiO UTWS5 (2025).
• In the box: LINK TWS earhooks, charging case, 0.78mm 2-pin connectors, USB-C cable, quick start guide, instruction card and warranty card.