Downmixing

In sound recording and reproduction, audio mixing is the process of combining multitrack recordings into a single track. These tracks that are blended together are done so by using various processes such as EQ, Compression and Reverb. The track may be mixed in mono, stereo, or surround sound. There are numerous approaches, methods and techniques involved in Audio mixing; some of these practices include levels setting, equalization, stereo panning, and effects. Audio mixing techniques and approaches can vary widely, and these can greatly affect the qualities of the sound recording.

Audio mixing techniques largely depend on music genres and the quality of sound recordings involved. The process is generally carried out by a mixing engineer, though sometimes the musical producer or music artist may assist. After mixing, a mastering engineer prepares the final product for production.

Audio mixing may be transferred onto a mixing console or digital audio workstation.

In the late nineteenth century, Thomas Edison and Emile Berliner developed the first recording machines. The recording and reproduction process itself was completely mechanical with little or no electrical parts. Edison's phonograph cylinder system utilized a small horn terminated in a stretched, flexible diaphragm attached to a stylus which cut a groove of varying depth into the malleable tin foil of the cylinder. Emile Berliner's gramophone system recorded music by inscribing spiraling lateral cuts onto a vinyl disc.

Electronic recording became more widely used during the 1920s. It was based on the principles of electromagnetic transduction. The possibility for a microphone to be connected remotely to a recording machine meant that microphones could be positioned in more suitable places. Even more useful was the fact that the outputs of the microphones could be mixed before being fed to the disc cutter, allowing greater flexibility in the balance.

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