Selecting Audio

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Most Audacity operations involve selecting a range of audio in one or more tracks, then deleting or moving the selection or applying an effect to it which changes its sound. The selection can be made by mouse or can be manipulated using only the keyboard. Selection of an exact range accurate to various selection formats (time units, samples or media frames) can be made using Selection Toolbar.

You have the flexibility to select entire multiple tracks (or only a range within those tracks). This makes your change affect the entire (or selected) range in all those selected tracks. Alternatively you could select all or part of an individual track, and then change each track in a different way.

Contents

  1. Selecting the entire project
  2. Selecting regions using the mouse - this is the usual way to make selections
  3. Selecting tracks using the mouse
  4. Selecting using the keyboard - visually impaired users will find this the best method to make selections
  5. Selection Toolbar - this enables you to make very precise selections
  6. Extending or contracting an existing selection
  7. Menu commands for selecting
  8. Listening to the selection
  9. Label Tracks - a useful way to recall particular selections
  10. Spectral selection



Selecting the entire project

You can select the entire length of all tracks on screen with Edit > Select > All or use the shortcut CTRL + A (or CMND + A on a Mac).

Selecting regions using the mouse

The easiest way to select a region of audio is to click and drag. If it's not already selected, choose the Selection tool Tool select.png from Tools Toolbar, below:

Tools toolbar basic7.png

Now click the left mouse button anywhere inside of an audio track, and click and drag to the other edge of your selection, and release.

If you have a Snap To option enabled in Selection Toolbar, this will force all mouse clicks and selections made with the mouse to snap to the current Selection Format.

Some tips:

  • You can drag from left to right or from right to left, it doesn't matter.
  • You can start your selection in one track, and end it in another track, and both tracks (plus the tracks in-between) will all end up selected.
  • If you move the mouse past the left or right edge of the window while dragging, Audacity will scroll the window in that direction as long as the mouse button is down.
  • ESC key aborts selection drags, and restores the previous time selection, frequency selection, and set of selected tracks.

Normally, you select both the tracks and the range simultaneously, by clicking and dragging. For example, to create the selection in the image below, make sure you're using Selection Tool Tool select.png, click in the track just after 2.0 seconds in the first track, then drag rightwards to just after 5.0 seconds as displayed on the Timeline, then downwards so that the gray selection region now includes the second track:

Clips017.png

Note that because the drag started in the first track and extended into the second track, only those two tracks are selected, as indicated by the darker gray color of the Track Control Panel. Therefore, any operation you perform will now only affect the selected area of the first two tracks.

Boundary Snap Guides

Boundary Snap Guides make it easy to make a selection that starts or ends at a physical boundary, like a label or clip. Whenever snapping is taking place, a yellow vertical line appears to indicate the snap location.

Warning icon Note carefully that this is distinct from the "Snap To" options in Selection Toolbar which snap selection edges (or the cursor) to time units, samples or media frames.

Selecting tracks using the mouse

There are two very useful things you can do by clicking in the Track Control Panel to the left of a track - make sure that you click in a neutral area, not inside one of the buttons or sliders. See Audio Tracks for more about the Track Control Panel.

Clicking on a track's Track Control Panel will select the entire track. That's a very easy way to apply an effect to an entire track. If you want to select all tracks, you can alternatively choose Select All from the Edit menu.

There's another handy way to select an entire track or clip: just double-click inside it.

If you hold down the SHIFT key while left-clicking on a track's Track Control Panel, you can toggle the selectedness of that track. For example, if you want to select the first and third tracks only, you could choose Edit > Select > All and then shift-click on the middle track to deselect it while leaving the others selected.

If you deselect all tracks (by toggling selectedness off in all tracks or by clicking in the gray background underneath the bottom track in the project), any region that was present will remain visible in the Timeline. This gives you a way to play this selection even though no tracks are selected.

Selecting using the keyboard

You can modify the selection entirely using the keyboard. The currently focused track is indicated with a glowing border, as you can see from the track called "Guest" in this image:

Focus1.png

To change the focused track, press UP or DOWN arrow. In this image, we pressed down arrow to change focus to the "Bkgnd" track:

Focus2.png

Once a track has focus, press ENTER or RETURN to change it from being selected to not selected, or from not selected to selected. Selections are only acted upon if the track containing the selection is itself selected.

If you only have a cursor position, but not a selection, pressing LEFT or RIGHT moves the cursor to left or right respectively, giving you a new cursor position from which to start a selection.

  • To create a selection starting from the cursor point, hold SHIFT while pressing LEFT or RIGHT arrow to extend the selection leftwards or rightwards respectively from the cursor point, or to further extend the selection.
  • If you extended the selection too far, hold CTRL + SHIFT while pressing LEFT or RIGHT arrow to contract the selection from the right or left edge respectively.

You can always use Selection Toolbar if necessary to find out if you have a selection (if there is only a cursor, the "Length" radio button will show a zero time value).

Once you have a selection, hold SHIFT while pressing UP or DOWN arrow to extend or contract the selection up or down tracks.

  • SHIFT + HOME creates a selection region from time zero in the project (on the timeline above the waveform) to the cursor point.
  • SHIFT + END creates a selection region from the cursor point to the end of the project.
  • Edit > Select > Track Start to Cursor (or shortcut SHIFT + J) creates a selection region in the selected tracks from the start of the leftmost audio track to the cursor point. The start of an audio track (the point where its blue waveform begins) does not have to be time zero.
  • Edit > Select > Cursor to Track End (or shortcut SHIFT + K) creates a selection region in the selected tracks from the cursor point to the end of the rightmost audio track.

Creating selections at an exact time

If you already know the exact times at which the selection should start and end, you can use the [  shortcut when the track is not playing, recording or paused to open the "Set Left Selection Boundary" dialog. Use the time digits to set the left-hand boundary of the selection as below. To change the Selection Format of the time units or frame boundaries, right-click (or use the keyboard Context Key) or left-click the downward-pointing triangle to right of the time digits.

  • If the cursor is currently to left of where the selection should start, advance the current position of the time digits to move the cursor rightwards to the correct start position. Then use the ]  shortcut to bring up the "Set Right Selection Boundary" dialog. Here you can set the time at which the selection should end, which draws the selection.
  • If the cursor is currently to right of where the selection should start, use [  if necessary to advance the time digits so as to place the cursor at the intended end of the selection. Then use [  again to set the left boundary of the selection which will draw the selection from that left boundary to your chosen end position.

Exact selections can also be created directly within Selection Toolbar by similarly manipulating the time digits.

Sometimes you may want to create a new selection using the start point (left boundary) of the current selection as the new end point, or using the current end point (right boundary) as the new start point. To do this, press LEFT arrow to place the cursor where the beginning of the selection was, or RIGHT arrow to place the cursor where the end of the selection was, in both cases removing the selection. Now create and adjust the new selection as above.

If you select "Nearest" (or "Prior") in the Snap To dropdown menu in Selection Toolbar, then using LEFT, RIGHT, SHIFT and CTRL as above will move the cursor or selection edge to the nearest (or previous) second, hundredth of a second, CDDA frame or any chosen selection format.

  • Use [ or ]  as above to force the cursor or selection to a position outside the current selection format, even if Snap To is enabled.

Selection Toolbar

Selection bar toolbar basic7.png

One handy way to keep track of what you've selected and to make very precise modifications is to use the Selection Toolbar. For our purposes here, let's concentrate on its main purpose, the Selection Start and End/Length boxes. By changing the radio button from "End" to "Length", you can display and control the length of the selection instead of the endpoint. Which one is useful for you depends on the circumstances: if you need a clip from a song that's exactly 30 seconds long, you may want to set the length to 30, and then modify the start until you have just what you want. Other times you may know the exact end time but need to figure out where to start, independent of the resulting length.

Selection Toolbar also displays and can move the cursor position without there being a region selected. To move the cursor to an exact position using Selection Toolbar, set the "Selection Start" and "End" boxes to the same value.

You can set the values displayed in the Selection Toolbar boxes using the mouse and/or keyboard. To change a particular digit in a box, click on it, or you can navigate to it using only the keyboard:

Navigating into and through the Selection Toolbar controls
Key Action
CTRL + F6 Move the focus to/from Selection Toolbar
TAB Move forwards through the Selection Toolbar controls
SHIFT + TAB Move backwards through the Selection Toolbar controls
LEFT / RIGHT Move cursor between digits or to/from End/Length

Once you have clicked on or navigated to a digit, it will highlight in white to show it is active, as shown in the image below:

30Seconds SelectionToolbar basic7.png

You can then increase or decrease the digit's value by scrolling the mouse wheel, by using UP arrow or DOWN arrow or by typing a new value over the existing value. After typing a value, the cursor automatically moves to the next digit and selects it, so you can type the required values one after the other. If you type the wrong digit(s) it can be convenient to use BACKSPACE which moves the cursor back to the previous digit and resets it to zero.

Working with the Selection Toolbar digits
Key Action
UP arrow Increase the highlighted digit
DOWN arrow Decrease the highlighted digit
BACKSPACE Move back to previous digit and reset it to zero. Use the DELETE or CTRL + K shortcut to delete selected audio while Selection Toolbar has focus.

As an alternative to navigating into Selection Toolbar, you can use the [ and ] shortcuts to move the cursor or create selections or to adjust existing selections.

Selection Formats

By default,Selection Toolbar lets you enter values in units of hours, minutes and milliseconds. This is appropriate and accurate enough for most purposes. However if you need for example to make a selection that is accurate to the nearest sample or is defined in CDDA or film frames, numerous other Selection Formats are available. To choose other formats, click the triangle to right of any box. You can also select in or right-click over any digit in a box (or use a keyboard equivalent).

Extending or contracting an existing selection

Once you have a selected range you can move either edge of the selection so as to expand or contract the selected length, or you may want to expand the selection at one edge and contract it at the other so as to select a similar length in a slightly different place; Audacity offers multiple methods to facilitate this:

  • Hover the mouse pointer near the edge of a selection, when you hover close enough to the edge the mouse pointer changes to a hand with pointing finger (indicating you can now click and drag the selection). Then click and drag with the mouse to move that edge of the selection.
ExtendSelection.png
If you want to turn off that feature, open Preferences, choose Tracks then uncheck "Enable dragging of left and right selection edges".
  • You can also extend or contract an existing selection by holding down the SHIFT key while left-clicking the mouse near one of the edges of the selection. The nearest edge of the selection will jump to the current position of the mouse pointer. This is really useful if you know exactly what you want to select but it doesn't easily fit on the screen at once:
  1. Click at one edge of the selection
  2. Scroll until the other edge is in view
  3. Shift-click to set the other edge of the selection.
  • Hold SHIFT while pressing LEFT or RIGHT to extend the selection from the left or right edge respectively.
  • Hold CTRL + SHIFT while pressing LEFT or RIGHT to contract the selection from the right or left edge respectively.
  • Use Selection Toolbar to precisely place the selection boundaries by entering their positions.
  • Use the [  or ]  shortcut when the track is not playing, recording or paused to open the "Set Left Selection Boundary" or "Set Right Selection Boundary" dialog respectively. Then adjust the position of the left- or right-hand selection boundary. As in Selection Toolbar, to change the Selection Format of the time units or frame boundaries, right-click (or use the keyboard Context Key) or left-click the downward-pointing triangle to right of the time digits.
Warning icon Mac users: remember to substitute the Command key for the Control key.

Including or excluding the existing range in other tracks

You can also change which tracks are selected independently of the range, so that selecting an extra track includes the selected range in that track, and deselecting a selected track moves the selected range out of that track. This gives you complete flexibility to extend, contract or move the existing range up or down between multiple tracks.

To change which tracks are selected without affecting the range, there are multiple methods.

  • Hold SHIFT while clicking on the Track Control Panel to the left of the waveform to toggle its selectedness.
  • Press UP or DOWN to change the focused track, then press ENTER to toggle its selectedness.
  • Hold SHIFT while pressing UP or DOWN arrow to extend or contract the selection up or down into adjacent tracks.

Use the first two of the above methods when you want to select or deselect non-adjacent tracks.

Note that it is possible to have a range selected but no tracks selected. In that case, you will only see the evidence of the selected range in the Timeline.

Advanced: If you enable Sync-Locked Track Groups you don't need to explicitly select other tracks so as to maintain synchronization when inserting, removing or time-shifting audio.

Menu commands for selecting

The Edit > Select menu has several commands that are useful for selecting.
Edit > Select > ... Action
All Select all tracks, including the entire content of audio tracks and note tracks.
None Deselect all tracks, removing any selection they contain and setting the cursor at the start of the former selection region.
Left at Playback Position Sets the left selection boundary at the current playback position, otherwise opens a dialog for moving the left selection boundary.
Right at Playback Position Sets the right selection boundary at the current playback position, otherwise opens a dialog for moving the right selection boundary.
Start to Cursor Select from the start of the track to the cursor position.
Cursor to End Selection from the cursor position to the end of the track.
Region Save Captures the currently selected range or cursor position.
Region Restore Restores the range or cursor position from Region Save.
In All Tracks Extend the current selection or cursor position up or down into all other tracks.
In All Sync-Locked Tracks Extend the current selection or cursor position up or down into all other tracks which currently have the Sync-Lock icon   Sync-lock icon.

Listening to the selection

With audio, it usually isn't obvious from the waveform what you want to select, so you really want to listen just to the left and right edges of a selection to make sure you are editing the correct part. Also because the purpose of multiple tracks is usually to mix them together as combined audio, by default the selected range plays for all the visible tracks, selected or not. To change this you can mute or solo individual tracks in the Track Control Panel.

But if you are new to audio editing, don't worry. For now, you can just click and drag to create a selection on a single track, and press SPACE to listen to all of it. Come back here for more help when you start to work on more advanced projects and are having trouble selecting what you want.

Selecting while audio is playing

Sometimes the easiest way to select an exact portion of audio is to mark the selection boundaries while you're playing (or recording) audio.

To do this, press the [  shortcut to mark the left edge of the audio, then the ]  shortcut to mark the right edge and draw the selection.

After you've done that, you'll definitely want to listen to the selection to make sure it was right. Press SPACE once to stop playback and then press SPACE again to hear just the selection. There are additional keyboard shortcuts that let you listen to just the beginning or end of a selection - see Special Playback Keyboard Commands for details.

Label Tracks

A useful way to retain a selection for future use is to label it; while the selection is highlighted press CTRL + B to label the selected region. For more information see Label Tracks.

Spectral Selection

Spectral selection is used to make selections that include a frequency range as well as a time range on tracks in one of the spectrogram views. Spectral selection is used with special Spectral edit effects to make changes to the frequency content of the selected audio. Among other purposes spectral selection and editing can be used for cleaning up unwanted sound, enhancing certain resonances, changing the quality of a voice or removing mouth sounds from voice work.

All of the time-based selection techniques (horizontal selection) are still available when doing spectral selection.

See the Spectral Selection page for more details.

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