FX-AUDIO/DAC-M3J with B/Hi-Res/No External Case/Board/Part 5. Please note that the photos are reused. Operation has been confirmed. This device converts digital audio from a computer or smartphone connected via USB to analog for high-quality listening. It's USB-powered, so no power supply is needed. Drivers are automatically recognized, so no download or installation is required. It's a Hi-Res compatible DAC & headphone amplifier. To use it, you'll need a USB cable and headphones (or earphones). When connected to USB, a blue LED lights up, and it blinks while playing music files. Turning on the blue boost switch enhances the bass for a powerful sound. It originally comes with a metal case, but it can be used as is. You can put it in a transparent case yourself, or make a case by modifying a Daiso bookshelf, and I think you can enjoy various DIY projects. 【Product Features】 ■ Hi-Res support with VT1620A ■ Power stabilization, made possible by bus power We have generously used more than enough audio capacitors to achieve stable performance, realizing bass that is unimaginable from such a small enclosure. ■ Philips TDA1308 is used for the headphone amplifier IC ■ with B!! Equipped with a bass boost function that can emphasize the bass, and can be switched ON/OFF with a switch. The full-fledged CR Bass Boost circuit provides a setting that allows you to experience a sufficient effect of +6dB at 80Hz and a remarkable +8dB at 30Hz, so you can fully enjoy energetic dance music and rock music. 【Main IC Specifications】 ■ Audio Controller IC (USB-DAC): VIA VT1620A Supported formats: Up to 24bit/96kHz ■ Headphone Amplifier IC: Philips TDA1308 SNR 110dB, THD+N 0.03%, Output power 40mW(THD+N < 0.1 %)