Slate

The term 'slate' comes from the silent film practice of writing the scene, take and shot numbers with chalk on a slate and holding it up in front of the camera before the action starts, so that the film editor can identify the material. A role now replaced by the 'clapper-board' which adds an audio synchronisation marking facility as well. In an audio context, a slate is a verbal identification recorded just before each take to help identify it subsequently. This is normally achieved by using a talkback microphone routed to the main, group and/or direct outputs of a mixer. The console slate function often mixed a low frequency tone in with the microphone signal to help make locating the start of each take much easier when fast-winding the tape against the playback head. Each slate ident would be heard as a short, steady mid-frequency tone.