The second essential piece of DJ equipment is to have alternating music sources. A DJ is expected to mix two recordings together flawlessly and to do that he needs (usually) two music sources. In vinyl this would involve having two record players, though some DJ’s gained notoriety for using three of more ‘decks’ in their music sets) that were played alternatively with different records one at a time. The industry standard has been Technic’s for these vinyl players for many years.

As the technology moved on to CD’s the DJ equipment had to change. Today there are very advanced CD players that allow a DJ to play the records alternating back and forth but also to add in scratch effects that older systems were incapable of doing.

With the advent of computer mixing it is now possible, through the use of specially developed music programs, to have just one device to alternate the music sources. Many DJs use this choice of equipment now for its versatility and compact nature. The laptop can be programmed to run two or more recordings at one time for the DJ to alternate between.  As an addition to these being used individually, many DJ’s use a combination of this equipment to achieve the sound that they want. One example of this is to use a laptop but to also hook up a vinyl player in order to perform some quite spectacular sound and visual effects of turntabilism.