OverviewThe FiiO KA17 USB DAC and Headphone Amplifier is a flagship dongle DAC and amp built for listeners who want desktop-grade performance in a pocketable device. Powered by dual ESS ES9069Q flagship DAC chips and a 16-core XMOS XU316 USB receiver, and driven by four THX AAA-788+ amplifier chips in a fully balanced configuration, the KA17 delivers detailed, dynamic sound whether on the go or plugged into a desktop rig via its dedicated Desktop Mode. Its 0.91-inch OLED display and physical buttons make it easy to monitor sampling rate, gain, and volume at a glance.Simcoe Audio Video InsightThe detail that separates the KA17 from most dongles is its second USB-C port: one handles data from your source device, the other accepts dedicated external power, and enabling Desktop Mode with that second port connected nearly doubles balanced output from 300mW to 650mW per channel at 32Ω. Without that second cable, you still get a legitimate 300mW balanced in Normal Mode, which is already more than most competing dongles offer. The 10-band PEQ is also genuinely useful here since it's adjustable through the FiiO Control app or fiio.com without needing the KA17 connected to a phone with the app installed, which is a nice touch if you mostly use it with a laptop or desktop.Best for the FiiO KA17: Run it in Desktop Mode with both USB-C ports connected when at a desk to unlock the full 650mW balanced output, and drop back to a single cable in Normal Mode for portable listening where 300mW balanced is still plenty for most headphones.More DetailsWhy It Wins Dual ESS ES9069Q DAC Chips: two flagship DACs handle the left and right channels independently for a cleaner, more detailed audio background than a shared single-DAC design. Quad THX AAA-788+ Balanced Amplification: a four-channel fully balanced amp circuit delivering up to 650mW+650mW (4.4mm balanced, 32Ω) in Desktop Mode. Desktop Mode with Dual USB-C: a dedicated switch and second USB-C port reconfigure the DAC, power supply, and amplifier for maximum output when connected to external power. What Makes It DifferentMost dongle DACs run entirely off the power delivered through a single USB-C data connection, which caps how much output power they can realistically deliver. The KA17's dedicated second USB-C port for external power lets it draw more current than a single-cable dongle can, which is how it reaches desktop-amp-level output (650mW balanced) while still fitting in a pocket for portable use.Technical Highlights PCM up to 768kHz/32-bit, DSD512 Native, and Full MQA Decoding: covers essentially every common high-resolution format without transcoding. SPDIF Output via 3.5mm Jack: the same jack doubles as a coaxial SPDIF output (up to 96kHz/24-bit) for feeding an external DAC. 10-Band PEQ via App or fiio.com: adjustable equalization without being tied to a phone with the FiiO Control app installed. Buyers GuideWho This Is For The Desktop-and-Portable Dual User: wants dongle portability during the day and a genuine power boost at a desk without switching devices. The High-Impedance Headphone Owner: needs the extra headroom that Desktop Mode's 650mW balanced output provides for harder-to-drive headphones. The Format Completionist: wants native DSD512 playback and full MQA decoding covered from a single dongle rather than juggling devices for different file types. Ideal Use Case Desktop Listening with External Power: both USB-C ports connected, Desktop Mode engaged, for maximum balanced output at a desk. Portable Listening on a Single Cable: Normal Mode still delivers a genuinely strong 300mW balanced output for headphones on the go. Feeding an External DAC via SPDIF: use the 3.5mm jack's SPDIF output to route a digital signal to a separate DAC. What To Pair It With High-Impedance or Planar Headphones: benefit most from the 650mW Desktop Mode balanced output. A Laptop or Desktop Computer with a Spare USB-C Port: needed to supply the second port's dedicated external power for Desktop Mode. The FiiO Control App or fiio.com: unlocks 10-band PEQ adjustment beyond the KA17's default tuning. Alternative OptionsIf you don't need the flagship dual-DAC design or Desktop Mode's power boost, the KA13 covers similar dongle DAC and amp duty at a more accessible level in FiiO's lineup. For a fully desktop-bound alternative without a battery-free portable form factor, the Q7 or K9 Pro ESS deliver comparable or greater output from a larger unit. The KA17 remains the pick when you want the most output FiiO offers from something dongle-sized.