Audio mixing is the process by which multiple sounds are combined into one or more channels. In the process, the source signals' level, frequency content, dynamics, and panoramic position are manipulated and effects such as reverb may be added. This practical, aesthetic, or otherwise creative treatment is done in order to produce a mix that is more appealing to listeners. Audio mixing is practiced for music, film, television and live sound. The process is generally carried out by a mixing engineer operating a mixing console or digital audio workstation.