Built for audiophiles, headphone enthusiasts, and creators who want one box that can power everything from sensitive IEMs to demanding planar-magnetics, the FiiO K17 is a professional-grade desktop DAC/headphone amplifier with a fully discrete Class-AB amplifier. The unit delivers up to 4000mW + 4000mW (balanced) with a dedicated DSP enabling a 31-band, studio-style PEQ you can tailor on the device or via companion software.
The K17 can be controlled and navigated from a responsive 3.93" touch display or with an IR remote for couch-friendly control. At the heart of the K17 lies the AKM's flagship combo (AK4191 + dual AK4499EX), which handles conversion up to PCM 768 kHz / 32-bit and DSD512 over USB. Additional connectivity spans Gigabit Ethernet, dual-band Wi-Fi, Bluetooth with LDAC/aptX family, AirPlay, and Roon Ready support. Additionally, there is local playback from a rear USB drive. The rear and front panels include a wide range of connectors including USB (front/rear), optical, coaxial, RCA, 4.4mm line-in, 4.4mm headphone outputs (1/4" and 4.4mm), and 4-pin XLR adapters. There are also balanced XLR and RCA line outputs for speakers or external amps, making the K17 a powerful all-in-one hub for a modern desk setup.
A Symphony of Retro Elegance and Modern Technology
Designed as a new-generation desktop DAC and headphone amplifier that is distinctive in both performance and character. Merging retro-inspired aesthetics with advanced engineering, the K17 delivers a unique look with extensive functionality. It serves as the upgraded successor to the K9 Pro while also pushing into new directions for high-end desktop DAC/amp products.
Specialty Chips for Hi-Fi Desktop Mixing
Inside the K17, an M21586Q DSP chip handles audio processing with double-precision 64-bit floating-point calculations at a 360 MHz clock speed. Working together with a high-performance ES9821Q ADC and a specially tuned ultra-low phase noise femtosecond crystal oscillator, this platform enables the 31-band high-precision lossless PEQ to be used in every mode while keeping the processed audio signal faithful to the original signal. The DSP also supports strong output-protection and is designed to safeguard connected headphones and other audio equipment.
31-Band High-Precision Lossless PEQ
Powered by DEL (Dual Engine Limiter) technology and proprietary algorithms, the K17's PEQ provides dynamic range compression (DRC), dynamic range expansion (DRE), limiter, and compressor controls. It can process PCM signals from 44.1 to 96 kHz directly in the PEQ without resampling, while allowing precise tuning with gain from +12 dB down to -24 dB and Q values from 0.4 to 128 dB. Users can use this equalizer to correct or emulate frequency-response curves, and PEQ presets can be exported, imported, shared, and stored, making it straightforward to adjust or simulate different headphone tunings.
Discrete Class AB Transistor Current Amplification Headphone Amplifier
The K17's headphone stage uses a fully discrete amplifier design built around an op-amp plus transistor current-amplification topology. It employs a pair of classic ON Semiconductor MJE243/MJE253 complementary transistors to deliver high current with low output impedance, providing up to 4000mW + 4000mW of balanced output power, almost twice that of the K9 Pro ESS. This lets the K17 comfortably drive many types of headphones and IEMs while keeping the sound pleasant, smooth, and natural.
AKM flagship DAC AK4191+ Dual AK4499EX
The K17 uses AKM's flagship DAC configuration, combining an AK4191 with two AK4499EX chips-one DAC per channel. Its 8-channel to 4-channel low-pass filter design helps reduce common-mode interference, improving stereo separation and dynamic performance. The architecture also separates digital and analog sections and employs the new DWA Routing technology to further clean up the background and enhance resolution.
Fully Balanced Desgin
From the DAC stage through the I/V conversion, low-pass filtering, and headphone amplifier, the K17's audio chain uses a fully differential circuit structure. This helps maintain a wide dynamic range and significantly lowers crosstalk between channels. Key stages such as the I/V conversion and LPF use multiple low-noise, precision OPA1612 op-amps to ensure strong and dynamic audio performance.
Physically Separated Boards
Within the K17, the power-supply, digital, and analog sections are placed on separate circuit boards to minimize interference between them. This layout supports accurate signal processing and contributes to a cleaner, more refined sound output.
Advanced Power
Precision power supply design
- The K17’s main power is provided by a custom, low-noise, high-quality transformer designed to keep the supply as clean as possible. This is backed by five 4700μF electrolytic capacitors that offer substantial energy reserves, helping to maintain a steady and reliable power feed.
Separate power supplies for analog and digital circuits
- The digital and analog sections of the K17 are powered independently, with separate supplies dedicated to each. This separation helps prevent crosstalk and other forms of interference between the two domains.
Multi-stage analog power supply
- The K17’s analog audio circuit is fed by a multi-stage power-supply system. Many sections, including the DAC, LPF, and transistor stages, have their own dedicated power-control circuits. Low-noise TPA7A47/7A33 LDO regulators with high PSRR then act as secondary regulators to provide consistently stable, clean power.
Dual-Core Design for a Smooth Stable Experience
The K17's system is driven by a high-performance X2000 multi-core processor that combines a main XBurst2 CPU core with two logic CPUs and an additional XBurst small core. This configuration provides strong computing capability with low power consumption, ensuring precise audio processing and smooth, stable playback. A low-power ESP32-S3 SoC is also used, featuring a high-performance Xtensa 32-bit LX7 dual-core CPU running up to 240 MHz plus an ultralow-power co-processor, helping deliver a responsive and fluid user experience.
Additional Detials
The K17’s industrial design combines square and circular elements into a coherent whole, blending retro-style elegance with a modern, tech-forward look. Practical considerations are integrated into the design too, such as multiple knobs positioned for easy control and a grid-style structure that aids in faster heat dissipation.
Touch controls
- A custom 3.93-inch LCD screen lets you quickly adjust settings and access various functions using touch input, providing an intuitive control interface.
Five control knobs
- The five front-panel knobs allow convenient operation: a single press can put the unit into standby, and the knobs also let you adjust volume, output gain, and other key settings quickly and easily.
Included infrared remote control
- The included infrared remote lets you change operating modes, select EQ presets, and adjust volume from a distance, offering more flexible and comfortable control options.
Listen without worry—multiple protection systems
- The K17 incorporates multiple protection mechanisms that can detect abnormal conditions and automatically take protective action to help prevent damage. These include protections for headphone-amp temperature, transformer temperature, output overload, output DC, and power-input overcurrent, allowing you to listen with greater peace of mind.
Wired or wireless—always online
- For wired networking, the K17’s Ethernet port supports up to Gigabit speeds for fast, stable data transmission. It also includes an AP6256 Wi-Fi module that supports both 2.4 and 5 GHz networks, offering a wireless alternative that can still reliably carry lossless audio.