The previous model is the CDJ-800MK2.
-Major differences with the previous CDJ-800MK2 model
Compared to the CDJ-800MK2, the CDJ-850 also supports USB devices, rekordbox and other brands of DJ software.
-Major differences with the higher grade CDJ-900 model
Compared to the CDJ-850, the CDJ-900 also supports LAN-LINK and rekordbox LINK and is equipped with a slip mode.
-Major differences with the lower grade CDJ-350 model
Compared to the CDJ-350, the CDJ-850 is equipped with an big jog dial with on-jog display, a wave display and a cue point memory function.