Audio Clips

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In Audacity, all audio is contained in clips.
  • Each clip can be moved around independently of other clips.
  • Clip names can be edited to make them more meaningful.
  • Clips can be trimmed non-destructively, that is without losing audio. The audio is just hidden and can be restored later.

Clips are contained in audio tracks.

  • An audio track can be empty but usually contains one or more clips.
  • All the clips in an audio track are affected by settings in that track, including:
    • gain/volume settings
    • pan settings
    • real-time effects
See Clips examples for an example of creating clips, and how they can be expanded.
Advice The images on this page have RMS display turned on, the light color in the center of the waveform.

Contents

  1. Channels, Clips and Tracks
  2. Trimming a Clip
  3. Renaming Clips
  4. Moving Clips
  5. Moving a Clip Between Tracks
  6. Time-stretching - changing the speed of clips
  7. Changing the pitch of clips
  8. Creating Clips - Splitting Clips
  9. Merging or joining Clips
  10. Navigating and selecting Clips
  11. Clip context menu
  12. Track colors
  13. Moving colored Clips
  14. Pasting clips or tracks into a different project


Channels, Clips and Tracks

The terms channel, clip and track can be a little confusing, especially because some applications may use them to mean slightly different things. Within Audacity, the meaning is as follows:

  • A channel is for audio recording (input) or playback (output). Audacity can record two channels of input (stereo), and more if you have a special sound card or audio device that supports more than two simultaneous channels. Audacity supports only two channels of playback (output), no matter what kind of audio hardware you have.
We won't talk about channels any more on this page. We just wanted to make it clear what the word "channel" means within Audacity.
  • A clip is a section of audio inside an audio track. Note that a non-empty audio track contains at least one clip.
  • An audio track is like one instrument in your symphony, or one voice in your podcast. You can add more tracks, and all of them will be mixed together to create your final output, but during editing you can manipulate each track independently. If you have an interview recorded with two microphones, each one can go in a separate track. If you have background music, that could go in a third track. If a track contains only one clip, you can move the entire contents of the track along the timeline. If the track is split into multiple clips you can move each of those clips independently.
The word "track" is often used to refer to a "song" as in "the third track on the CD" or "the latest track from MyFavouriteBand". Just remember that the word "track" has this specific meaning within Audacity (and all other music production software).


Trimming a Clip

Drag at the upper edge of the clip handle to move it

You can trim a clip by dragging near the upper corner of its left and right edges. Alternatively you can use Edit > Remove Special > Trim Audio.

  • Doing so will hide the waveform that goes beyond it (as opposed to fully deleting it).
  • If you make some edits to the clip and then later decide to un-trim it, you can just grab the upper corner again and extend it.
  • The hidden parts will not be played or exported.
  • Effects applied to a trimmed clip will not affect the hidden parts of the trimmed clip, only the visible portion of the clip is affected.
Tip Note carefully that there is no visual cue to indicate that a clip has hidden audio data.


Renaming Clips

Clips initially take their name from the track in which they are created. The clip names can be edited to make them more meaningful.

To edit a clip name double-click in the clip-handle drag-bar and the clip name will open up for editing.

Alternatively you can select the clip, then right-click in the clip and use the context menu which has an entry for Rename Clip.


Moving Clips

To move a clip, simply drag and drop it using the Clip-handle drag-bar (the light area with the rounded corners) at the top of the clip.

If you have snapping turned on the moved clips will snap to your preferred snap time format.

MoveClip.png

To move multiple clips at once, select all of the clips you want to move using the Selection ToolSelection Tool, then drag a Clip-handle within the selected region to move all selected clips. This will also move the selection area with it.

If you click a Clip-handle drag-bar outside of the selected area, the selected area will stay where it is and you'll only move one clip.

Tip Note that moving clips can make use of the yellow Boundary Snap Guides (also seen in the chapter on Audacity Selection). When you move a clip, Audacity will snap the left or right boundary of a clip to the nearest edge of a clip in any other track marking it with a yellow vertical line, making it very easy to line up clips during editing.

Moving stereo Clips

Time-shifting a clip in a stereo track will move both channels equally and this applies even if the clips in the two channels are not synchrous that is do not fully line up or are sepatate.

Tip If you want to move clips in a stereo track independently from each other, you need to split the stereo track into mono tracks first.

Moving to negative time

If an audio track is dragged to the left (earlier on the Timeline) audio data may be hidden before the start of the track. This is indicated by the presence of two arrows at the left edge of the track.

Audio before zero.png
Audio before time zero is not exported unless that audio is explicitly selected.

Or unless Export Multiple is used with "Split files based on Tracks". In this Export Multiple by tracks case, the entire audio of each track is exported, including that behind zero, regardless of any selection.

Preference for "Editing a clip can move other clips"

There is a preference setting in Tracks Behaviors Preferences that controls whether following clips to the right cab or cannot move when editing to the left of them.

  • When this is checked "off" (default setting) "Editing a clip can move" pins clips so that they cannot move in response to an edit in another clip. When removing content, any following clips will not be allowed to move back. When pasting, an error message will display if there is not enough room to paste without moving the following clips.
  • When this is checked "on" (non-default setting) if the track has been split into more than one clip, any clips following to right of the edit point can always move as necessary in response to pasting, cutting, deleting or other change that adds or removes content.

See Preferences settings that affect Edit behavior for details of what this setting does.

Tip Sync-Lock trumps (over-rides) this setting.

If you have Sync-Lock enabled in the Tracks Menu, then clips can move even when this setting is turned "off".


Moving a Clip Between Tracks

You can drag and drop on the clip-handle drag-bar to move a clip to a different track, but there must be room for the clip between the clips on the second track.

The clip can't go in the small gap between the clips, but it can go behind them


Time-stretching - changing the speed of clips

You can change the speed of the clip by holding Alt and dragging near the upper corner of its left and right edges, note that the cursor changes when you do this. Doing so will also change the pitch of the clip.

Note carefully:
  • when you apply an effect to a time-stretched clip the changed speed of the clip will be automatically rendered,
  • if you apply an effect or generator to a selection within a time-stretched clip then Audacity will split the original clip so that the the selection can be rendered as part of applying the effect.
Advice Time-stretching may affect stereo image:
  • If you time-stretch a stereo clip where the left and right channels have nothing, or little, in common then the algorithm used for the stretching is likely affect your stereo image, losing the stereo separation.
  • The audio will still be intact but stereo information/separation may be lost.
Tip You can workaround this by:
  1. Split the stereo track to mono
  2. Time-stretch each of the two clips by exactly the same amount the yellow snap guides will help with this exact alignment.
  3. Render the clip stretching on each track separately.
  4. Re-join the two mono tracks to be a stereo pair from the context menu in the Track Control Panel of the upper track.

Changing pitch and/or speed

Alternatively, you can select the clip and then right-click in it to get the context menu which has a Pitch and Speed command which enables you to set a precise changed pitch or speed.

Selecting this command will cause the following dialog to be displayed. You can change the pitch by semitones and cents, and/or enter any % speed change, by typing in the Pitch and Speed box.

With this context menu commend the speed and pitch of the audio clip can be changed independently.

This is unlike the effect Change Speed and Pitch where changing the speed also changes the pitch, and the only control is the speed.

Clip Pitch and Speed.png
Tip You can change the pitch dynamically with this dialog while Audacity is playing, but you cannot change the speed during playback.


Changing the pitch of Clips

You now can non-destructively change the pitch of a fully-selected clip by holding Alt and pressing the Up and Down arrow keys.

You will see a visual cue at the right hand end of the clip which indicates the pitch change in number of semi-tones.

Clip pitch change.png

This will not change the speed of the clip, only its pitch.


Creating Clips - Splitting Clips

See Clips examples for an example of creating clips, and how they can be expanded.

When you record some audio or import audio from a file, you get a single track containing one clip. In many cases there are natural gaps in the audio - silence between sentences or pauses between phrases in music. Those are good candidates for splitting the track into multiple clips, allowing you to move or otherwise manipulate those clips independently. There are several ways to create multiple clips in a track.

  • Edit > Audio Clips > Split to split the clip at the current cursor position or selection region.
    • Right-click > Split clip context menu to split the clip at the current cursor position or selection region.

The following commands only work on a selection region in an existing track or clip:

  • Edit > Audio Clips > Split New moves the selected audio to the same position in a new track at the bottom of the project.
  • Edit > Remove Special > Delete and leave gap removes the selected audio without shifting the following audio.
  • Edit > Remove Special > Cut and leave gap removes the selected audio to the Audacity clipboard without shifting the following audio.
  • Edit > Audio Clips > Detach at Silences creates clips either side of absolute silences.

The following operations will create a new clip:

  • Edit > Paste; creates a new clip at the paste position.
  • Edit > Duplicate; creates a new clip in a new track based on the current selection.
Tip It's easy to select all the audio of a given clip.
  • make sure that Selection Tool, the I-beam, is enabled in Tools Toolbar then double-click in the clip,
  • you can also select all of an entire track that contains only one clip in this way.


Merging or joining Clips

Adjacent clips may be merged into one clip by selecting across one or more split lines then using Edit > Audio Clips > Join to join the clips into one.

Alternatively you can select the clip, then right-click in the clip and use the context menu which has an entry for Join Clips.


Navigating and selecting Clips

An entire clip can be selected by left-clicking anywhere in its waveform.

A number of menu items and corresponding keyboard shortcuts can be used to select and navigate between clips.

Making selections in clips:


Navigating between clips


Clip Context menu

Right-clicking in the waveform of the clip will cause the clip's context menu to be displayed:

:Waveform context menu 3-5-0.png You can use this to:
  • Cut, Copy or Paste audio selections
  • Split or Join Clips (based on the current selection)
  • Mute or Unmute the audio track
  • Rename the currently selected clip
  • Change the pitch and/or speed of the currently selected clip
  • Render the changed speed of the currently selected clip


Waveform colorways

You can optionally change the colorway of the waveforms displayed in your project. The setting is per track and not per project so you can have multiple colorways in the same project as in the image below.

Four colorways are available with the color selection made from the dropdown menu in the track's Track Control Panel.

Waveform colorway 3-1-0.png


Moving colored Clips

A Clip takes on the selected color of the waveform that it originates in.

When a clip is moved into a different colored track, the clip retains its original color.

Moving a colored clip - before.png
Blue clip in the top track with sufficient space in the bottom, red track
Moving a colored clip - after.png
The blue clip has been moved into the red track and retains its blue color
Tip Changing the color in the Track Dropdown Menu will change the colors of all clips in that track, regardless of their current colors.

This does make it a bit awkward if for example, you have a track:

  • blue clip - blue clip - red clip - blue clip
and you want:
  • green clip - green clip - red clip - green clip
You will need to move the red clip temporarily to a new track while they change the blue clips to green clips.


Pasting clips or tracks into a different project

When pasting clips or tracks (or selections from them) into a different project you will be offered the opportunity to copy the entire smart clips (including any hidden audio data they may have) or just the selected audio:

Paste smart clip dialog.png

These settings can also be changed in Tracks Behaviors Preferences.

Tip The default setting is to copy the entire smart clip, this can vastly increase the size of the data in the target project.

So consider carefully if just the selection is all that you are likely to need in the future.

Advice The figure reported for the audio data size is always the figure for the full source clip and not the size of the selection, regardless of which option you choose.