FiiO QX13 black

The FiiO QX13 is the first model in the Chinese manufacturer’s new QX series. This portable digital-to-analog converter uses an ESS SABRE PRO ES9027PRO chip, typically found in home audio systems, paired with six Texas Instruments operational amplifiers. It offers a desktop mode delivering up to 900 mW per channel. The device features a 21-layer carbon fiber chassis, an approximately 2-inch color display, and a magnetic mounting system. It weighs 33.7 grams.

Carbon fiber construction and sophisticated engineering

The QX13 chassis is composed of 21 layers of carbon fiber stacked and compressed, a manufacturing technique borrowed from aerospace and motorsport. This composite material provides remarkable structural rigidity while keeping weight to a minimum. The surface receives an ultra-clear UV varnish that improves grip while preserving the characteristic texture of woven carbon. An alternative aluminum-alloy version with laser engraving is also available for those who prefer a more traditional metallic finish.

The 1.99-inch IPS display is a rarity in this product category. Protected by third-generation Corning Gorilla Glass, it shows the audio format, volume, and operating mode in real time and provides access to advanced settings. A dedicated 32-bit processor handles the user interface with multiple customizable themes, usable in both portrait and landscape orientations. The three physical buttons located below the screen offer direct tactile control of volume and playback, with multiple functions accessible via long or double presses.

The internal architecture physically separates the digital and analog circuits onto two distinct boards, each with independent electromagnetic shielding. Additional insulating sheets are placed at strategic points to minimize interference. Thermally conductive silicone dissipates heat from critical components to the chassis, enabling stable performance even during prolonged use at full power.

Professional-grade conversion and amplification technology

At the heart of the QX13, the ES9027PRO chip represents the second generation of ESS Technology’s SABRE PRO series, initially developed for professional audio equipment and high-end home hi-fi systems. This single chip configures its eight conversion channels in parallel, four for each stereo channel, thereby optimizing the signal-to-noise ratio and conversion precision. Two ultra-low-noise ES9312 regulators independently power each group of channels, ensuring precise matching and drastically reducing clock jitter.

The amplification section relies on six carefully selected Texas Instruments operational amplifiers. Four INA1620 chips, integrated at the silicon-die level, benefit from an internal layout specifically designed to eliminate inter-channel crosstalk, even under extreme usage conditions. Two OPA1692 amplifiers complete the circuit, providing high current capability with reduced power consumption. This cascaded configuration includes LPF voltage amplification, a BUF current boost, and reinforced parallel current expansion.

The USB interface is built around the 16-core XMOS XU316 processor, a solution typically reserved for desktop converters. Paired with two femtosecond crystal oscillators with minimal thermal drift, this processor handles audio streams with ultra-low latency while supporting the most demanding formats. Compatibility ranges from 32-bit/768 kHz PCM to native DSD512, with full MQA decoding and support for UAC 1.0 and 2.0 modes for universal compatibility with computers, smartphones, and game consoles.

Desktop mode and intelligent power management

The QX13’s desktop mode dramatically transforms its capabilities. Accessible via a physical switch on the side of the device, this mode dynamically adjusts internal supply voltages and amplifier circuit parameters. In standard mode, the QX13 draws power only from the main USB port, deliberately limiting consumption to preserve the source device’s battery life. Activating desktop mode literally unleashes the device’s capabilities, increasing balanced output power from 605 mW to 900 mW per channel into 32 ohms.

A second USB-C port, identified by a red marking, allows connection of a dedicated external power source. This dual-supply configuration separates circuit power from data transmission, enabling the QX13 to operate at full power without draining the connected smartphone or tablet’s battery. The system includes a precision power meter that analyzes in real time the power delivery capabilities of each USB source, automatically adjusting gain and output power accordingly. The screen displays this information as a dynamic bar graph, allowing instant visualization of actual consumption.

Compatibility with the FiiO E-Stick external battery further expands the possibilities. This 1100 mAh cylindrical battery connects directly to the side power port and slots into a specially designed combined case. The QX13 can even charge the E-Stick via its main port when connected to a charger, creating a complete modular ecosystem for high-performance on-the-go listening.

Advanced user interface and personalization

The FiiO Control app, available on Android and iOS, along with a dedicated web interface for computers, unlocks the full potential of the QX13. The 10-band parametric equalizer provides precise control over the sound signature, with independent adjustments for frequency, Q factor, and gain for each band. Custom profiles can be saved directly to the QX13’s internal memory, allowing instant recall of preferred settings without relying on a smartphone.

The onboard menu, accessible from the touchscreen, offers a wealth of options rarely seen on a device this size. Five digital filters subtly shape the sound to suit listening preferences. Left-right balance can be finely adjusted to compensate for potential hearing asymmetries or unbalanced recordings. Volume offers two step modes, 60 or 120 increments, for more or less granular control depending on needs.

The 3.5 mm jack output includes a surprising function: it can be switched to a digital S/PDIF output via the menu, instantly transforming the QX13 into a USB-to-S/PDIF converter. This versatility allows integration into complex audio chains, for example connecting a computer to a vintage amplifier equipped only with coaxial digital inputs.

Magnetic system and mobile integration

The supplied leather case integrates magnets compatible with Apple’s MagSafe system and the Qi2 standard. For recent iPhone users, the QX13 snaps directly to the back of the phone through its case, creating a compact and elegant setup. Android users get an adhesive magnetic ring to stick on their smartphone or case, replicating the same functionality. This approach eliminates the annoyance of a dongle dangling freely at the end of its cable.

The included USB-C cable deserves special mention. Unlike the generic cables often bundled with dongles, FiiO provides an 8-core braided cable combining single-crystal copper and silver-plated copper. At 10 centimeters in length, it offers the flexibility needed to place the QX13 comfortably while minimizing clutter. Two silicone dust caps protect unused USB-C ports, a practical detail to preserve the device’s longevity.

The included screen protector and multiple interface themes reflect a strong focus on user experience. Each theme optimizes readability according to lighting conditions, with options for automatic brightness dimming to preserve the source device’s battery life.

Technical specifications

Digital-to-analog conversion

• Main DAC: ESS Sabre ES9027PRO 8-channel
• Regulator: ES9312
• Architecture: Hyperstream IV
• USB interface: XMOS-316
• Supported formats:
  • PCM up to 32-bit / 768 kHz
  • Native DSD up to DSD512

Amplification

• Amplification stages:
  • 4 × Texas Instruments INA1620 (low crosstalk)
  • 2 × OPA1692 (high current, low power consumption)
• Maximum output power:
  • 4.4 mm balanced output: 900 mW into 32 Ω (desktop mode, high gain)
  • 3.5 mm single-ended output: 440 mW into 16 Ω (desktop mode, high gain)
• Gain settings suitable for high-impedance headphones and sensitive IEMs

Audio performance

• Frequency response: 20 Hz – 90 kHz
• Total harmonic distortion: 0.0004 – 0.0006%
• Signal-to-noise ratio: up to 124 dB

Connectivity and outputs

• Input: USB-C (compatible with PC, Mac, smartphone, tablet)
• Single-ended headphone output: 3.5 mm mini-jack
• Balanced headphone output: 4.4 mm jack
• S/PDIF output via 3.5 mm connector

User interface

• 1.99-inch color display showing volume and audio resolution
• Physical control buttons
• Dedicated Android app:
  • 10-band equalizer
  • 8 DSP filters
  • Gain and channel balance adjustment

Build

• Materials: aluminum chassis (black) or carbon fiber (titanium)
• Dimensions: 30 × 64 × 13 mm
• Weight: 33.7 g (carbon fiber) / 39.2 g (aluminum)
• Magnetic attachment to the back of a smartphone

General information

• Included accessories:
  • USB-C to USB-C cable
  • Carry pouch with magnetic mount
  • Screen protector film
• Certifications: Hi-Res Audio, DSD, ESS Sabre DAC
• Compact, lightweight, and portable form factor
• Award-winning in the specialist press