The American Audio 19MXR from ADJ is a ground breaking 4-channel preamp Midi mixer with built-in 4 x 4 Sound Card so DJs can play and mix music from their favorite computer software, yet still have the hands-on hardware control from a compact, 4-channel mixer. Plus with a built-in Sound Card DJs can start mixing right away without having to purchase extra equipment. All the features found on the 19MXR were intuitvely designed for the most experience DJs by fellow DJs. Features such as; Balanced Outputs, Long-life Optical Fader and Reverable Crossfader and channel Faders with adjustable curve. The crossfader was factory tested for over 1 million crossfades back-and-forth and never quit working!