DJ mixer

A DJ mixer is a type of audio mixing console used by DJs to make smooth transitions between different sound recordings as they are playing. The sources are typically record turntables, compact cassettes, CDJs, or DJ software on a laptop. DJ mixers allow the DJ to use headphones to preview the next song before playing it to the audience. Most low- to mid-priced DJ mixers can only accommodate two turntables or CD players, but some mixers (such as the ones used in larger nightclubs) can accommodate up to four turntables or CD players.

DJ mixers are usually much smaller than other consoles used in sound reinforcement systems and sound recording; a typical DJ mixer may have only two to four inputs, while most small to mid-sized live sound and recording mixers have 8 to 12 input channels, with large live sound and recording mixers having 48 or more input channels.

The key features that differentiate a DJ mixer from other types of audio mixers are the ability to redirect (cue) a non-playing source to headphones, in order to find the desired part of a song and the presence of a crossfader, which allows for an easier transition between two sources. A crossfader has the same engineering design as a fader, in that it is a sliding control, but unlike faders, which are usually vertical, crossfaders are usually horizontal. DJ mixers typically have phono preamplifiers to hook up turntables. DJ mixers are also used to create DJ mixes, which are recorded and sold. DJ mixers usually have equalization controls for bass and treble of each channel. Some 2010-era DJ mixers have onboard electronic or digital effects units such as echo or reverb. Some DJ mixers also feature a built-in USB sound card to connect to a computer running DJ software without requiring a separate sound card. DJ mixers typically have a microphone input, so that a microphone can be plugged into the mixer, enabling the DJ to announce songs or act as an MC for an event. Some DJ mixers have a kill switch.

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