FIIO K15 from an authorized Japanese USB DAC with headphone amplifier and AK4497S [Ships retailer] FIO-K15 built-in headphones, (Silver)

FIIO's first product to feature the AK4497S. Rich detail and immersive sound: The K15 is FIIO's first product to use two AK4497S chips with upgraded "VELVET SOUND" audio technology. These chips deliver low distortion, wide dynamic range, and expanded signal bandwidth with low power consumption. Rich detail in both the low and high frequencies delivers a natural, immersive sound experience. *About VELVET SOUND: VELVET SOUND is the brand that embodies AKM's sound philosophy for new-generation audio products. By leveraging the full potential of audio technology, we aim to achieve "realistic sound reproduction" and deliver an authentic, immersive sound experience without compromise. Discrete Class AB Headphone Amplifier. Powers everything from full-size headphones to IEMs: The K15 features a discrete Class AB headphone amplifier circuit that employs an operational amplifier and transistor current amplification design. It incorporates a pair of ON Semiconductor's standard transistors, the MJE243G/253G, to generate high current with low output impedance. This discrete circuit delivers up to 3000mW of balanced output power, easily driving everything from full-size headphones to in-ear monitors, producing a smooth, natural, yet melodic sound. Supports streaming, local, analog, and digital audio. Various audio sources on one device: ・Streaming Media: Enjoy various streaming services via AirPlay. ・Local Playback: Supports USB external storage* and allows you to listen to your own music collection. ・Single-Ended Line Input: Supports RCA single-ended analog audio input and is amplified by the K15. ・Balanced Line Input: Supports 4.4mm balanced analog audio input and is amplified by the K15. ・USB DAC: Equipped with an XMOS 16-core XU316 chip, it supports 768kHz/32bit, DSD512, and full MQA decoding*. ・Bluetooth Decoding: Supports SBC/AAC/aptX/aptX LL/aptX HD/aptX Adaptive/LDAC. ・Optical Decoding: Supports optical digital input and functions as an optical digital decoder. ・Coaxial Decoding: Supports coaxial digital input and functions as a coaxial digital decoder. *MQA full decoding is only available when the USB input is set to EQ=OFF. When in bypass mode and EQ = ON, MQA is not available. *The maximum current output of the USB-A port is 500mA, which is suitable for USB flash drives. If you need to connect a portable hard drive, please connect a separate power source. Equipped with a 10-band high-precision lossless PEQ: The 10-band high-precision lossless PEQ allows you to simulate and correct the frequency response of your headphones using the dedicated app or online. It also has functions for exporting, importing, sharing, and saving EQ curves. *The PEQ function is effective for USB, coaxial digital, optical digital, Bluetooth, streaming, and local playback. Multiple protections ensure a safe listening experience: Headphone amplifier temperature protection, output overload protection, overvoltage protection (OVP), output DC protection, and power input overcurrent protection are all implemented to intelligently detect abnormal conditions and prevent damage to the device, allowing you to enjoy your music with peace of mind. Fully Balanced Audio Circuit: From DAC decoding, low-pass filtering, gain control, and headphone amplification, the K15's audio circuitry is fully balanced, ensuring a wide dynamic range while effectively reducing crosstalk, minimizing noise, and improving audio output quality. Stable Wired and Wireless Network Connections: The Ethernet port supports Gigabit speeds for fast and stable data transmission, while the AP6256 Wi-Fi module supports 2.4G and 5G wireless networks for stable lossless audio transmission. Dual Master Cores for a Stable and Smooth Experience: ・High-Performance Multi-Core Processor X2000 This processor features a unique design with two main CPU cores, "XBurst2" and a secondary core, "XBurst0," providing excellent computing performance with ultra-low power consumption. This ensures accurate audio signal processing and ensures stable and smooth music playback. ・Efficient MCU ESP32-S3 This chip integrates a high-performance Xtensa 32-bit LX7 dual-core processor and an ultra-low-power co-processor with a clock speed of up to 240MHz. This chip enables precise system control for a high-precision, high-speed user experience. As the successor to the popular K9 model, this model has been significantly improved with two of AKM's latest DACs, the AK4497S. It features a high output of 3000mW, eight input modes, and an easy-to-use 10-band PEQ. It offers performance approaching the professional sound quality of the higher-end K17 model, all at a great price. A legitimate evolution of the K9, this next-generation headphone amplifier with built-in DAC combines practicality with excellent sound quality.