While digital technology has changed the way DJs access and choose songs to spin, it also had the effect of changing what songs were used in battle routines. Old battle routes were vinyl only routines, meaning the DJ had to spend countless hours digging through vinyl records and marking off specific portions of it for use with sticker and markers. By the time their routine was done, they would have a small collection of records, maybe six to ten of them in a pile waiting to be cued up. If the DJ had access they could even compile their own temporary use “dub plates” for their battle routines.
Today, the art of digging for records doesn’t exist to a battle DJ. Instead, they are more willing to create their own battle records in a production setting. This allows them to skip the record flips and changes, and go directly to the technique and musical aspect of battling. Some of the smarter DJs even go through the trouble of optimizing what sounds they already have. This means sending them off to get mastered; compression is used to increase the attack of bass notes and an overall sense of “professionalism” seems to come through the music quality.
http://www.attackmagazine.com/reviews/gear-software/fxpansion-dcam-dynamics/