This cool little customer, the FiiO E17 USB DAC Headphone Amplifier, puts audiophile-grade punch into your headphone experience—hook it up between your music player, smartphone or PC for a deeper, sweeter sonic ride. There is a standard 3.5mm output for your audio earwear. Inputs are high-end S/PDIF coax/optical with a 192K/24bit sample rate, mini USB with 96K/24bit, and standard 3.5mm line in. All of that adds up to flexibility and HiFi quality. If you feel the need to tweak, bass, treble, gain and balance controls are at your fingertips. The bright OLED display is two-colour. Charge the Li-ion battery for up to 15 hrs use via USB or FiiO’s own port for their L7 dock and E9 desktop amp—it’s solo, or it’s a system.