3 Groups of Stereo RCA Input: with input switch knob, can switch multi-way input signal losslessly. As a preamp, it can greatly improve the sound quality, with large dynamic, rich details, smooth and clear sound. With HiFi Sound and Tone Control: more smooth and delicate sound can be enjoyed by adjusting treble, mid and bass knob, and bypass function(turn high knob to the leftmost end) is added to turn off the tone control and enjoy original sound, adding much fun and higher playability.
eBay