Pyle Home PHE7AB USB DAC and Portable Headphone Amplifier Black USB audio decoding and output for PC, functioning as a high quality external USB soundcard - Easy to use digital volume control function with great precision and channel balance Texas Instruments' PCM2706 serves as USB receiver. For better sound quality, a Wolfson WM8740 serves as digital-to-analog convertor (DAC), pairing with a high performance operational amplifier from ADI for the DAC circuit Built-in headphone amplifier utilizing AD8692 and Texas Instruments' TPA6130A as pre- and power-amp for high performance, good resolution, low distortion, and powerful output - Built-in EQ for 3 levels of Bass Boost Standard 3.5mm stereo line-in jack for portable amplification with conventional audio source - Built-in rechargeable 1050 mAH Li-ion battery for 80 hours of continuous operation Dual 3.5mm headphone output jack. Convenient design makes it easy to share music between two listeners - Quality anodized aluminum satin finish case design, small and compact, ideal to be wrapped together with digital audio player