A system where manual control of a process is replaced or enhanced by computer control, such as mixing desk automation where faders, mutes, and equalization can be controlled in part or in whole by a computer. In write mode, the automation system produces a continuous record of all the actual fader settings and adjustments made by the engineer during a mix. Most systems allow changes on replay, while remembering and recreating previous manipulations of other tracks. The level changes are recorded and recreated by VCAs in each input module of the console. The VCA-produced data can be recorded directly onto a track of the multitrack tape, giving a continuous record of all mixdown fader settings. Or, the VCA outputs can be recorded onto a separate disk. In the latter system, alignment of the fader data with the multitrack master tape is achieve by referring to a common SMPTE timecodetime code recorded on the tape and disk systems. See mute modemute-writenull-pointread modesnapshot automationupdate modewrite mode.