The Hercules DEEJAY TRIM 4&6 plus Scratch Starter Kit is an interface with time-code DJ software that includes the Hercules DeeJay Trim 4&6 Audio Interface, Virtual DJ 6 LE Time Code software, 2 time-coded vinyl discs, and 2 time-coded CDs. This package is ideal for analog DJs who want to use their CD players and turntables to mix MP3 files, or for a computer-based DJ who wants to use their computer"s music library when mixing on CD players and turntables. What is time-code DJing? Time-code DJing involves mixing audio files stored in a computer and controlling the playback with turntables or CD players. The process occurs when the DJ plays special time-coded discs on vinyl turntables or CD players whose output signal is digitized in real time by the audio interface. This signal tells the DJ mixing software where you are in the track and the speed of the playback so that the software can duplicate on MP3 files the actions the DJ performs on the time-coded discs. The advantages of time code DJing are: the DJ can use the same gears to mix computer audio files as CDs or vinyl discs with instant access to the computer audio library (meaning faster access than the time it takes to find and load vinyl discs or CDs)the increased accuracy of the vinyl turntable or the jog wheel of the CD player (the wider the wheel, the better the accuracy)and the ability to switch easily between computer audio files and vinyl discs or CDs. Advantages of timecode DJ mixing: Easy to learn for advanced DJs: DJs who have their own DJ gear (CD players/turntables/analog mixer) don’t need to learn how to use new DJ gear to mix computer audio files: they mix on the CD players, turntables and analog mixer they already know, and they control the computer audio files with the same gear (CD players/turntables/analog mixer) as if the tracks were on CDs or vinyl records.