Editing Audio With Audacity
Quick Key Stroke Guide
Play – space bar
Pause – P
Zoom in – Cmd/Ctrl1
Zoom out – Cmd/Ctrl3
Slice – Cmd/Ctrl I (if it doesn’t work the first time, make sure you are in the select tool and click where you want it to be.)
Copy – Cmd/Cntrl C
Cut – Cmd/Cntrl X
Paste – Cmd/Cntrl V
Undo – Cmd/Cntrl Z
Save – Cmd/Cntrl S
Join two split clips – select using the select tool, Go to Edit > Audio Clips > Join
Move two separate clips – select using the select tool, then Shift K and drag them
– Move a clip by selecting the top bar and a hand should appear.
– A yellow box should show up around the track you are working on. If you don’t see it on the track, click in the track to select it.
Settings
Two factors that determine the quality of digital recordings are sample rate and sample format or size. Generally you will be working with a sample rate of 44 Hz and a sample format of 16 bits.
Sample Rate is important to audio files for two reasons. Sample Rate is the number of times per second you capture a snapshot of audio information during recording. Higher sample rates result in great audio detail, the same way you get smoother motion in video by capturing more frames per second. On playback, it’s necessary to know the sample rate for compatibility with output specifications. — Changing Audio Sample Rate in Audacity
Audio formats
For editing .wav or .aiff are best as they are not compressed as much as .mp3 files. However, once you are done editing, for posting online .mp3 is the best format. Audacity does not support .wma (Windows Media Audio) or MPEG4 used by iTunes.
Creating a new project
When you start or open a new file, you must Save Project As. Audacity will create a AMU file which will contain all of your edits.
Check preferences
44.1 kHz is the default sample rate
16-bit wav file to export
Under File Formats, choose “Make a copy of file before editing.”
Ways of Opening and Importing audio files
1) Drag and drop the file on to the application
2) Select File>Open or Project>Import
You import a file when you already have an open project and wish to add a new track. Audacity can import WAV, AIFF, AU, IRCAM, MP3 and OGG
Cryptobotany interview example
Tools Overview
Recording with Audacity
1) Create a new project, File>New
2) Choose the input: built-in input or built-in microphone through Preferences.
3) Click record, then pause to pause, stop to stop
4) Notice the levels on the upper-right hand corner
Reference: At this site, you can review the entire menu with explanations by Audacity
Cut, Copy, Paste and Trim
1) Make a selection. Click the selection tool in the tool bar. Press and hold the mouse as you select an area of the file with the tool.
2) Press the space bar to listen to the file.
3) You can extend the area of your selection or contract it by holding down the shift key. (You will see a white hand pointing the way.)
4) Cut the selection by choosing Edit>Cut or Ctrl/Command X. This places the audio on the clipboard.
5) To paste that selection else where in the track or another, put the cursor at the desired spot and type Ctrl/Command X or select Edit>Paste.
6) To delete a section of the file, select it and click delete or select Edit>Delete.
7) To copy a section of the file, select the portion and Ctrl/Command C or Edit>Copy. This will leave your original intact.
8) If you want to cut everything but your selection you can do so using the Edit>Trim command.
9) To split a track, use Cmd or Ctrl I.
Silence, Duplicate and Split
1) You can use the Edit>Silence command to replace a selection of the audio with silence.
2) Edit>Duplicate makes a copy of your selection and places it in a track beneath.
3) Edit>Split moves the selected portion of the audio into its own track and is replaced by silence in the original track.
Select All, Start to Cursor, Cursor to End
1) Edit>Select>All selects all of the audio in all of the tracks
2) Edit>Select>Start to Cursor selects all of the audio from the start to the cursor
3) Edit>Select>Cursor to End selects all of the audio from the cursor to the end of the file
Effects: fades, amplification
1) Use the envelope tool to create fade in and fade outs.
You can also select the portion of your audio you wish to fade and go to the Effects menu item where you can select “Fade In” or “Fade Out.”
2) To increase the volume, select the portion of audio using the selector, and go to Effects >Amplify. A popup box will show the suggested amplification. Don’t select “allow clipping.”
Undo, Redo, History
1) You can undo any actions by going to Edit>Undo or by clicking Ctrl/Command Z or by using the undo (counterclockwise arrow) in the tool bar. You can undo all the way back to your first action. You can also open up the History panel, View>History, and view your steps and undo specific steps.
Exporting file, exporting selection
For the moment, we are going to export our files as .wav (we need an extra plugin for mp3 and instead will use iTunes or online converters like zamzar.com or to create mp3 files.). To export your final edit, go to File>Export As WAV. If you want to export one selection of a file, select File>Export Selection As WAV.
Combining Audacity Files of Different Sample Rate
Audacity assumes that the first clip you add into the project is the correct sample rate and applies this to all additional files. This can be a problem if you have clips with different sample rates.
To fix this, you need to change the sample rate of each clip to the project rate.
Import all of your clips up in the project file.
Make sure the sample rate is what you want it to be, ideally 44 Hz, and click Export Multiple. Make sure that the format is wav, click “Export”. This will transform all of your files into the 44Hz sample rate.
Now, reimport then in a new project and they should all read 44 Hz.
In this lesson, we are using Audacity, which is a free, open-source software you can download from http://audacity.sourceforge.net/.
Quick tutorials:
Audacity Official Guide
Audacity Guide I
Audacity Guide II
Digital Recorders