Audacity

Audacity

Audacity is an audio editor and recorder available for Windows, macOS and Linux operating systems.
You can use it to:

• Record live audio
• Convert records/tapes into digital format
• Mix multiple audio sources together into a multi-track project etc

If you are now starting to work with audio, and you need some basic skills to record and edit files, Audacity with its tools is a good option.

Why Audacity?

• Simple to use and lightweight
• Has several tools and functions that cover your basic needs in editing
• Its price is free
• It is FOSS - free and open-source software

Free and Open-Source Software

Audacity is free, open-source software. You are free to use it for any personal, commercial, or educational purposes, including installing it on as many different computers as you wish. You are also free to give it away, sell it, or modify it for your own use, under the terms of the GNU General Public License.
The authors of Audacity decided to release it under the GPL for many reasons. Some do so out of generosity. Some do it for moral reasons because they believe that all software should be free;
Audacity being free means also that it will be more popular and useful. Another reason is to encourage collaboration. Because of Audacity's free license, multiple people worldwide have contributed code, bug fixes, documentation, and graphics.
Like other FOSS, it has online documentation and a community you can participate (ask questions, exchange knowledge etc).
Browse Audacity forums if you like: https://forum.audacityteam.org/

Basics

Download and install Audacity

• https://www.audacityteam.org/
• DOWNLOAD AUDACITY button (It will download the latest version of Audacity)
• Choose the operating system you are using. (Windows, macOS, GNU/Linux)
• Follow the installation instructions

Import audio

Import existing audio into Audacity. Can open many of the most common file formats like WAV, AIFF (uncompressed audio formats) or MP3, Ogg Vorbis (compressed audio formats) etc.
1. File > Import > Audio...
If you select the File > Import > Audio... command, then choose one or more audio files, Audacity will import the selected file(s) into the existing project. This is useful to bring the content of one or more audio files into a project that already contains audio (for example, to mix several audio files together).
2. File > Recent Files (Open Recent on Mac)
This command imports a single file from a list of the 12 most recently imported files or recently saved projects. The file opens in a new window exactly as File > Open....
3. Drag and drop files into an open Audacity Project window.

Select and Zoom

• Waveform: Audio in Audacity shows up as a Waveform. These jagged lines of peaks and valleys (high and low points) make up the waveform.
  

This is the visual representation of sound waves; time is represented horizontally from left to right, and the loudness of sound is represented vertically.
The louder the sound, the taller the waveform.

• Mono & Stereo files: In stereo, we can have separate audio in the left and right channels. In mono, there is only a single channel and you hear the same audio on both left & right sides.
• Mute & Solo
• Start, stop, pause: Play button or Spacebar to start and stop! Pause button or (p) key to pause.
• Selection tool: default tool to work with waveforms. Allows you to select specific sections. Eg you may need this to focus on editing a specific part or remove the selected part. Adjust the selection by holding (shift) or moving the cursor at the edges of the selection.
• Zoom tool: Lets you zoom in specific sections of the waveform by clicking. Helps for precise editing, like chopping a word or a breath and reorganising them. Zoom out by holding (shift) and clicking. To view the whole project as a whole, you can click the "Fit project to width" button. To zoom vertically: View->Zoom->Advanced Vertical Zooming and click on the left side of the waveform.

Playback controls

• Playhead: vertical line that you can place by clicking somewhere on the waveform. Hit the spacebar to playback from this point on.
• Loop: select a section with the select tool and hit Shift & Spacebar.
• Timeline: Clicking on a point of the timeline above the Waveform, playback will immediately begin.
• Jump to end or beginning buttons
• Record button

FFmpeg library

Audacity has by default some limitations on the types of audio file formats it can import and export. To have a much larger selection of file formats you can work with:
Go to Edit->Preferences->Libraries. If you don't have already the FFmpeg library, follow the download instructions according to your operating system.

• Installing FFmpeg for Mac: https://manual.audacityteam.org/man/installing_ffmpeg_for_mac.html
• Installing FFmpeg for Windows: https://manual.audacityteam.org/man/installing_ffmpeg_for_windows.html
• Installing FFmpeg for Linux: https://manual.audacityteam.org/man/installing_and_updating_audacity_on_linux.html#linff

Basic Editing

Make selections

• In a multi-track project, solo the first track. Soloing mutes all other tracks so you don't hear them while working on the solo track. You can unmute other tracks as well, to hear specific selections of sound. You can decide how you like to do that by unmuting/or soloing etc several tracks.
• To make a change to a track, I first have to select it.
• Let's say you want to remove a part of the audio. You can let the audio play and when you arrive at the point you want to cut, hit the "[" on your keyboard. When you arrive at the point that you want to cut you can hit the "]" of your keyboard. That will select the audio part in between the brackets "[]".
• You can also make selections across tracks. You can click on the first track, drag down and select the next one too.

Cut, copy, paste

You can cut, copy and paste snippets of audio in Audacity.

• Copy: Select an audio snippet. You can copy it by clicking Edit->Copy from the menubar, or you can ctrl+c (or command+c for mac)from your keyboard. Just as in text editors.
• Paste: You can paste this snippet on the same or another track by Edit->Paste, or Ctrl+V (or Command+V for mac) from your keyboard. Or you can paste it into a new track.
• Duplicate: Instead of selecting, copying and adding a snippet of audio on a new track, you can automate this by clicking Edit->Duplicate from the menubar, or you can ctrl+d (or command+d for mac)from your keyboard. That will separate the selected audio and put it automagically in a new track. You can use this duplicate to try effects on it etc.
• Cut: Select and cut an audio snippet from your track. Edit->Cut or ctrl+x (or command+x for mac) from your keyboard. This "regular" cut will remove the part that was cut and the rest of the waveform on that track jumps to the left to fill in the space where the cut part was.
• Split Cut: Maybe you want to cut a piece of audio but you want the rest of the waveform to remain where it was. (for example for synching reasons with other tracks). To do this, click on Edit->Remove special->Split Cut. For keyboard: windows-> alt+ctrl+x . mac-> opt+cmd+x. So this way it cuts the selection leaving a gap where it was and now we have 2 separate clips on each side of the gap.

Split clips

You may need to split a track into separate clips. This way you can play around with the timing, add a pause, shorten a pause etc.

• Split a clip: take the selection tool, and place the playhead where you want your split to occur. Then choose Edit->Clip Boundaries->Split. Keyboard command: ctrl+i (command+i for mac). Now we have two separate clips.
• Join two clips: Use the selection tool, and drag a selection that touches all the clips you want to join. Edit->Clip Boundaries->Join. !Be aware that if there is any space between the separate clips, audacity will not remove the space, but will convert it into silence. If you don't want this silence to appear, you need to use the "time shift tool" and drag until they snap together.

Envelope tool

• Use the envelope tool for volume automation. It is used for controlling a track's volume smoothly over time. Maybe you want your background music for example to decrease in volume when spoken word comes in. Select the envelope tool. Then you can place control points along the lines on the track and drag them up or down.
• Auto-ducking

- Select the track(s) or region(s) whose volume you want to modify (for example, a background music track).
- Deselect the track that is to act as the control track (for example, a spoken commentary). Note that the first unselected track underneath the selected track(s) acts as the control track.
- Place the tracks so that at least one of the selected tracks to be modified is above the unselected control track.
- The control track should be properly synchronized with the tracks to be "ducked" - you can use Time Shift Tool to align the tracks with each other as required.
- Choose "Auto Duck" from the Effect Menu.

Common effects

Look at the "Effect" menu, there are various effects and filters you can apply to your project. Some of the effects that are frequently useful are:

• Fade Out: Select the area where you want to apply the fade out. Effect->Fade Out. There are no more parameters to choose from. You can try out different selections (shorter-longer) and decide what works best.
  

!Tip: Audacity always remember the last effect you applied, so you can just use Effect->Repeat Fade Out for example.

• Fade In: Same as fade out: Effect->Fade In. They are pretty simple effects without a lot of control on the exact points of fade etc like in other audio editing programs.
• Amplify: Change the volume of an audio part. May be useful when some parts of a track are quieter than others, or when you want to balance the volume of different tracks in the same project. Select the area you want to adjust the volume, Effect->Amplify. You need to figure out how many decibels you want to "increase" or "decrease". Usually, you can try out different settings to see what works for you. You can also choose a negative value to decrease the volume.
• Change Tempo: You can change the tempo of an audio track, without changing the pitch. Select the audio, Effect->Change Tempo.
• Change Speed: Slow down or speed up an audio track, but here it will also change the pitch. Select the audio, Effect->Change Speed.
• Change Pitch: Change the pitch of the audio, but keep the same speed/tempo. Select the audio, Effect->Change Pitch. Maybe you want to create a chipmunk voice or a low monster voice.

Volume and envelope tool

more here
ducking and auto-ducking

Basic effects

Fade in/out
Amplify
Change tempo, change speed, change pitch
Paulstretch
Reverb
Noise reduction ---> reduce and residue
Generating silence or tone