FiiO QX11 Compact Headphone Amplifier

The FiiO QX11 is a compact USB DAC and headphone amplifier that goes well beyond a typical dongle. Two ESS ES9069Q DACs, an all-Texas Instruments amplifier stage and separate digital and analogue boards play PCM up to 768kHz/32-bit and native DSD512. A second USB-C port unlocks FiiO’s patented Desktop Mode, with up to 800mW per channel from the 4.4mm balanced output, and passes up to 45W of charging through to your phone. A colour screen, a built-in microphone and dedicated gaming sound modes make it as good for calls and games as for music.

Dual ES9069Q DACs and a modern USB processor

Two flagship ESS ES9069Q DACs, based on ESS’s fourth-generation 32-bit HyperStream architecture, give high performance with low power use. Their lower internal digital noise means a very quiet background, letting fine detail come through. USB is handled by the SPV5068, a RISC-V dual-core audio processor built for low latency, wide compatibility and efficiency: it uses as little as 150mW when decoding, has a 140dB digital dynamic range, and runs the QX11’s 1024-point FFT digital signal processing for EQ at up to 384kHz/24-bit.

An all-TI amplifier with clean, separate power

Building on the KA17’s high-performance design, the QX11 uses two TI OPA1692 op-amps for voltage gain and four OPA1622 op-amps in parallel for the headphone output, for very low noise and distortion and plenty of drive. A four-stage precision power supply filters ripple and noise step by step, with separately partitioned, low-noise LDO supplies for the digital and analogue circuits, the same approach used in desktop headphone amplifiers. The digital and analogue sections sit on separate boards under a shielding cover, so they can’t interfere with each other.

Desktop Mode: small size, big power

Connect a USB power adapter or a battery such as FiiO’s ESTICK to the orange POWER IN port and switch on Desktop Mode (FiiO’s patent ZL202321946664.8). Output rises from 360mW to 800mW per channel into 32Ω from the 4.4mm output, and from 175mW to 295mW from the 3.5mm, enough for in-ear monitors and the great majority of full-size headphones (FiiO recommends 8–350Ω). The same port can charge your phone, player or tablet at up to 45W over USB PD while you listen, or charge an ESTICK.

All at high gain, THD+N <1%; there’s also a low-gain setting. At its best (4.4mm, Desktop Mode) the QX11 measures a 126dB signal-to-noise ratio, THD+N below 0.00043% and 114dB crosstalk.

Hi-Fi and gaming, with a microphone

Switch between Hi-Fi mode and Gaming mode. Gaming mode adds four tuned sound effects (FPS, ACT, MOBA and music games) that bring out cues such as footsteps. The built-in microphone, CTIA in-line headset support on the 3.5mm output and AI environmental noise cancellation (ENC) keep your voice clear on calls and team chat. With headphones on the 4.4mm output, the built-in mic can still be used, and Gaming mode adds desktop sound pickup.

Screen, knob and shortcut button

The 1.14-inch colour screen, large for this class, shows the format and sample rate, volume, gain, filter, EQ and Desktop Mode at a glance, in landscape or portrait themes. The machined volume knob has double-sided 3D engraving and a press function, and FiiO rates it for more than 100,000 presses and 100,000 rotations. A new shortcut button can be set for single, double and long presses: EQ up or down, mode or theme switching, screen rotation or track skipping (by default: theme, mode and next track).

Tune it your way

The FiiO Control app offers 10 preset sound profiles and a 10-band PEQ at up to PCM 384kHz/24-bit, and AUTO EQ (in the app and on FiiO’s web platform) applies a profile matched to your headphones automatically. Firmware updates arrive over USB.

Good to know

• Desktop Mode needs power on the second USB-C port: a USB adapter, a power bank or FiiO’s ESTICK battery.
• The coaxial (S/PDIF) digital output shares the 3.5mm socket.
• In Desktop Mode at high gain the QX11 gets warm: FiiO measured surface temperatures of about 40–44°C in a 30°C room.
• In the box: QX11, protective leather case, short USB-C to USB-C cable, USB dust plug, quick start guide and warranty card.