Audio mixer

In audio, a mixing console is an electronic device for combining (also called "mixing"), routing, and changing the volume level, timbre (tone color) and/or dynamics of many different audio signals, such as microphones being used by singers, mics picking up acoustic instruments such as drums or saxophones, signals from electric or electronic instruments such as the electric bass or synthesizer, or recorded music playing on a CD player. In the 2010s, a mixer is able to control analog or digital signals, depending on the type of mixer. The modified signals (voltages or digital samples) are summed to produce the combined output signals, which can then be broadcast, amplified through a sound reinforcement system or recorded (or some combination of these applications).

Mixing consoles are used in many applications, including recording studios, public address systems, sound reinforcement systems, nightclubs, dance clubs, broadcasting, television, and film post-production. A typical, simple application combines signals from two microphones (each used by vocalists singing a duet, perhaps) into an amplifier that drives one set of speakers simultaneously. In live performances, the signal from the mixer usually goes directly to an amplifier which is plugged into speaker cabinets, unless the mixer has a built-in power amplifier or is connected to powered speakers. A DJ mixer may have only two channels, for mixing two record players. A coffeehouse's tiny stage might only have a six channel mixer, enough for two singer-guitarists and a percussionist. A nightclub stage's mixer for rock music shows may have 24 channels for mixing the signals from a rhythm section, lead guitar and several vocalists. A mixing console for a large concert may have 48 channels. A mixing console in a professional recording studio may have as many as 96 channels.

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