Graham Slee Bitzie USB Digital-to-Analog Converter Compact and portable high performance USB DAC and headphone amp Incredible natural sound quality and stereo imaging with no harshness and glare Headphone amp with 2 headphone sockets: 3.5 mini-jack & 1/4 inch jack - drive both low and high impedance headphones and IEMs Real rotary fine quality ALPS analoge volume control Supplied stereo RCA jack adapter connects to and drives active speakers, home audio and power amps