Phantom YoYo PCM2704 USB DAC USB Power Fiber Optic Coaxial Analog Output sz-11 Raspberry Windows 7 Pi Need No Driver Power supply voltage: 5 V (USB power supply) Distortion: the THD + N: 0.006% (RL &gt; 10 k ) Distortion: the THD + N: 0.025% (32  RL =) Signal to noise ratio: 98 dB /Dynamic range: 98 dB Headphone output power: 12 mW (RL = 32 )