I have the HA-P50 now very satisfied since 6 weeks and am. I often hear through headphones, as a player usually a smart phone, sometimes the computer. The HA-P50 is also a DAC and a headphone amplifier. The sound is impeccable and very accurate, in my opinion, better than the audible signal directly from the smartphone or the iPod Classic. He works well with iPhone, iPod Classic and Android (with the latest version tested). The HA-P50 drives smoothly also my Hifiman HE-500. He is also very well made, very compact, fits comfortably in your hand. The battery life with Apple sources is specified by the manufacturer, Android uses the HA-P50 battery for charging (why?). I would buy it again, because here price / performance value and the part does exactly what it should, and that too very well.