Sync-Locked Track Groups

Peter 22Feb13: WIP - working-title only - proper title to be decided later.

• ToDo-2 The position of the "misconceptions" alert note on page to be decided.

The Sync-Locked Tracks feature is enabled by the "Sync-Lock Tracks" menu item or button. It ensures that length and position changes occurring anywhere in a defined group of tracks (a Sync-Locked Track Group) also take place in all audio or label tracks in that Sync-Locked track group even if those tracks were not selected. This lets you keep existing audio or labels synchronized with each other even when carrying out actions like inserting, deleting or changing speed or tempo.

This command does NOT enable you to select a set of tracks and Sync-Lock them. Sync-Lock Track Groups are defined by their position within the project and their relationship to label tracks beneath them as described below.

Sync-Lock Tracks

Sync-Lock Tracks can be turned on, or off, at Tracks > Sync-Lock Tracks or by using the Sync-Lock Tracks button () in Edit Toolbar ; Sync-Locking is off by default. Turning on Sync-Lock Tracks does nothing itself, rather it sets the future behavior of Audacity when working with selected Sync-Locked Track Groups.

The button is shown as recessed when Sync-Lock Tracks is set to "on".

The Sync-Lock Tracks setting that you choose is a global one that applies to all Audacity projects, not just the curent one,unless and until you subsequently change the setting.

Sync-Locked Track Groups

Any audio track in Audacity can be in a group of one or more adjacent tracks that can be Sync-Locked with other tracks in that group. To form a Sync-Locked Track Group the tracks must be adjacent to each other, they may be terminated with a Label Track. If you require multiple Sync-Locked Track groups in your project then only the last one may be without a terminating Label Track, all the preceding ones must terminate in a label track to delimit them from the next following Sync-Locked Track Group. A Sync-Locked Track Group may have multiple label tracks as long as the label tracks are together at the bottom of the group.

When Sync-Lock is on an icon () shows bottom right in the Track Control Panel of each track in a Sync-Locked Track Group provided at least one of those tracks is selected. The icon denotes all tracks that will be affected when a menu operation in a selected track inserts or deletes audio (or otherwise changes the audio's position on the Timeline). The unselected tracks that will be affected are denoted by a patterned "Sync-Lock" selection in the waveform (a wallpaper with clockfaces) instead of the dark gray of a normally selected track.

Selecting Groups for Sync-Locking

Selecting at least one track from within a Group will mark that particular group as Sync-Locked, the icon will appear in the Track Control Panel of all the tracks in that Group. If you have multiple Groups then clicking ao a track in a different groyp will cause the Sync-Lock selection to move to the new group.

Peter 22Feb13: probably a 3-group example image to go here

• Gale22Feb13: Sliding is an edge case that shows Sync-Locked Track Groups working even when no tracks are selected or Sync-Lock Selected. I don't think we should use that example. A much better example may be something like deleting audio in front of a label and moving the labels back in the affected tracks.

Using Sync-Lock Tracks

The following links demonstrate in more detail the use of Sync-Locked Tracks in Audacity for common editing tasks:

• Using Sync-Locked Track Groups for Editing audio

• Using Sync-Locked Track Groups for Time Shifting audio

• Using Sync-Locked Track Groups for Time Stretching audio