Audio mixing is the process by which a multitude of recorded sounds are combined into one or more channels, most commonly two-channel stereo. In the process, the source signals' level, frequency content, dynamics and panoramic position are commonly being manipulated and effects such as reverb might be added. This practical, aesthetic or otherwise creative treatment is done in order to produce an elevated mix that is more appealing to listeners.
Audio mixing is done in studios as part of an album or single making. The mixing stage often follows the multitrack recording stage and the final mixes are normally submitted to a mastering engineer. The process is generally carried out by a mixing engineer (a mixer), though sometimes it is the musical producer who mixes the recorded material.
Prior to the emergence of DAWs (Digital Audio Workstations), the process of mixing used to be carried out on a device known as an audio mixer, sound board, desk, or mixing console. Nowadays, more and more engineers and independent artists are using a personal computer for the process (commonly referred to as mixing in-the-box).
Mixing as we know it today emerged with the introduction of commercial multitrack tape machines, most notably the 8-track recorders that were introduced during the 1960s. The ability to record sounds into a multitude of channels meant that treating these sounds can be postponed to a later stage - the mixing stage.
See main article: mixing console.
A mixer, or mixing console, or mixing desk, or mixing board, or software mixer is the operational heart of the mixing process. Mixers offer a multitude of inputs, each is fed by a track from a multitrack recorder; mixers would normally have 2 main outputs (in the case of two-channel stereo mixing) or 8 (in the case of surround).
Mixers offer three main functionalities:
Outboard gear (analog) and software plugins (digital) can be inserted to the signal path in order to extend processing possibilities. Outboard gear and plugins fall into two main categories:
The process of mixing often accounts for a few mixing domains: