NuPrime uDSD Hi-resolution USB-powered Portable DAC (PCM 384, DSD 256) & Headphone Amp USB sampling rates: 44.1,48,88.2,96,176.4,192,352.8,384KHz and DSD 2.8,5.6,11.2MHz. Discrete USB audio receiver and D/A converter, with coaxial S/PDIF output Asynchronous transfer mode for doubled jitter-reduction at data input and over-sampling filter stage Headphone output: max 140mW x 2 @ 32 ohm USB powered, no external power supply required. Works with Windows 7/8 and Mac OS