works great and like new. ESS SABRE Hyper stream DAC for the best file conversion * High performance 140mWat32 Ohm headphone amplifier * Supports virtually all file formats including DSD256 and up to 24bit/384kHz PCM * USB-powered, no external power supply required * Supports Windows and Mac * Ess sabre hyper stream DAC for the best file conversion * High performance 140mwat32 ohm headphone amplifier *Supports virtually all file formats including dsd256 and up to 24bit/384khz PCM *Usb-Powered, no external power supply required *Supports windows and mac