FiiO QX13 pairs ESS conversion with six TI op-amps

The FiiO QX13 is a portable USB DAC and headphone amplifier pairing an ESS ES9027SPRO DAC with six Texas Instruments op-amps and up to 900mW per channel of balanced output into 32Ω in desktop mode. A 1.99-inch color display provides access to playback information and settings, while 10-band parametric EQ lets you adjust frequency response for different headphones. Separate USB-C connections for audio and external power accommodate listening from a phone, computer, or externally powered desktop arrangement.

Eight DAC channels with dedicated power regulation

The ES9027SPRO uses a fully differential architecture with eight DAC channels operating in parallel. Two ES9312 low-noise regulators supply the conversion stage, while dual femtosecond crystal oscillators provide timing for different sampling rates to reduce clock jitter. The XMOS XU316 USB processor supports PCM up to 768kHz/32-bit, native DSD512, and full MQA decoding.

Amplification with two power modes

Four TI INA1620 chips and two OPA1692 op-amps handle analog amplification and current delivery. Each INA1620 integrates a dual-channel audio op-amp, eight precision-matched thin-film resistors, and an EMI filter. Balanced output reaches 605mW per channel into 32Ω in non-desktop mode and 900mW per channel into the same load in desktop mode.

A dedicated side USB-C port accepts external power, while the front USB-C connection carries audio data and power. The QX13 assesses the connected USB source’s power capabilities and adjusts amplifier gain and output accordingly. Separate digital and analog boards, an intervening shielding cover, EMI sheets, and thermally conductive silicone address circuit isolation and heat transfer during operation.

Parametric EQ with a defined playback limit

The 10-band parametric equalizer is accessible through the Android FiiO Control app or FiiO’s web-based controls. You can create custom profiles, use built-in presets, or explore community tunings to adjust your headphones’ frequency response. With PEQ enabled, playback supports PCM up to 192kHz/24-bit.

A display for playback and operating controls

The 1.99-inch IPS display shows playback format, volume, and operating status. A 32-bit processor runs customizable themes with portrait and landscape viewing options, and third-generation Corning high-strength glass covers the screen. Selectable 60-step and 120-step volume scales let you choose the adjustment resolution.

Additional controls include gain, digital filters, channel balance, display brightness, and a maximum volume limit. Temperature regulation and DC output regulation provide further operating safeguards.

Headphone, coaxial, and console connections

The QX13 provides 3.5mm single-ended and 4.4mm balanced headphone outputs. The 3.5mm connection also supports coaxial S/PDIF output, allowing the QX13 to pass digital audio to an external DAC. UAC 1.0 mode adds compatibility with devices including Nintendo Switch and PlayStation 5.

Availability

The FiiO QX13 is available now on Apos.