Appendix B. Glossary of Terms

AIFF, MP3, WAV —these are all common audio file types. You can import or export audio in these formats into and out of Audacity. However, only Audacity will be able to open files of the AUP file type.

Amplify—the process of increasing (or decreasing) volume of an audio track (or a portion of it).

Appending—adding an additional piece of audio at the end of an existing track, or to another project.

Bit or Sample Rates—computers use a unit of measure called bits. Bit or sample rates are the number of computer bits that are processed per unit of time, and are expressed in kilobits per second (kbps), or 1,000 bits per second. The higher bit or sample rate, the better the quality of your recording.

Click—short, disruptive sounds in an audio recording, most commonly heard on vinyl records. These show as spikes in the waveform.

Clip—is a short segment of audio. It can be combined with others to make an audio track.

Control toolbar—contains common icons used for any audio device: Play, Pause, Record, Skip to Start, Skip to End and Stop. These are the basic controls for recording and playing back the sound that you recorded using Audacity.

Decibel (dB)—a measurement of sound. It is a logarithmic unit used to describe the ratio of the signal level. Because it is logarithmic and not linear, its measurement scale doesn't increase by intervals of one. Instead each interval grows by a larger interval than the previous one. For example, a common ratio would be 10, so that the marks on the scale would read: 1, 10, 100, 1000, 10000, and so on.

Effect—artificially created or enhanced sounds, or sound processes used to emphasize certain portions of an audio track. You can add or apply effects to an audio track.

Editing Toolbar—contains all of the tools available for editing audio tracks in Audacity.

Export—the process of saving audio in another format other than that of the program you created it in. Typically, for audio, you will export in a WAV or MP3 format.

Hertz (Hz)—a unit of measurement used to describe frequency or tone. One single hertz is one audio wave cycle from crest to crest. The human ear can hear frequencies ranging from 20 Hz to 20 kHz.

LAME—an Audacity library plug-in that allows you to encode (or digitize) MP3 files. LAME is a high-quality MPEG Audio Layer III (MP3) encoder.

Library—a collection of audio files or tracks. Can be grouped by content of the audio files (like a music library) or just by the location of where they are stored.

Library Plug-ins—additional software modules that, when installed, expand the exporting capabilities of Audacity. Some libraries let you encode (or digitize) MP3 files, MPEG, and other audio file formats.

Main menu—(in Audacity) provides access to the basic functionality of the Audacity software.

Metadata or Tags—information about the recording, such as the artist or creator name, track title, genre, and album title.

Mixer toolbar—the toolbar in Audacity that is all about volume.

Mixing—the process of combining many tracks of different types of audio into a single recording.

Noise—unwanted sound of any kind, especially unintelligible or dissonant sound that interferes with the main audio in a track.

Normalize—to force all audio tracks to be of the same volume.

Overdubbing—having sound of any kind that plays (or is recorded) over the previously recorded track.

Pitch—sounds or tones are essentially regular, even-spaced waves of air molecules, as we see in the Audacity timeline. Audibly, we notice sounds as being higher or lower than others—this difference in sound is pitch.

Visibly, we see this difference by the spacing of the sound waves; the shorter the wavelength (from top to bottom), the higher the sound or pitch; the longer the waves, the lower the sound. Think of pitches as musical notes (like middle C and F sharp)—each has definite frequencies.

Plug-Ins—are extra features that can be added on top of the features of Audacity. Some plug-ins can make special sound effects or analyze audio content, and others just add to the long list of effects already available with Audacity.

Podcast—a simple audio track that is recorded, exported from a project, and then posted on a blog, or podcast site for downloading by others.

Preferences—are set up when you start a new Audacity project. They define the project's bitrate (quality), how we are going to export it, and what types of devices will be used when we record the project.

Project—when you open Audacity, you will open or create a new project (the AUP file). It includes all of the files, timing, and information on how you combined and edited different pieces of audio in order to make it into your file or project. This term isn't specific to audio editing, but to software that combines pieces of different files into one unit to create a final output.

RSS reader—is an acronym for Really Simple Syndication (RSS). It is type of web format that is used to publish frequently-updated items, such as blog entries, news headlines, audio, and video. If you use an RSS Reader, it checks the RSS feed web addresses regularly for new updates, and then alerts you when new content, such as podcasts, is available.

Sibilant sounds—a sound near or around an "s", "sh", and "ch" that hisses and distracts for the rest of the recording. A sibilant sound can be corrected through the use of proper editing in Audacity.

Silencing—lets you take out noise. Only you aren't actually deleting anything from the timeline, you just silence the noise.

Skype—a software application that lets you make voice and video calls over the Internet. These calls are made to other users of the service for free, or to landlines and mobile phones for a small fee. You can also use Skype for instant messaging, file transfer, and video conferencing.

Tags or Metadata— see Metadata or Tags

Tempo—the speed at which the audio track should be played.

Timeline—follows the horizontal of the audio track. Specifically, it shows a measurement of time for the entire length of the track.

Tools toolbar—gives you control options in the recorded audio's timeline. From this toolbar you can select audio, envelope sound, draw, zoom into the timeline, use Time Shift, and use the multi-tool option.

Track—one continuous audio element.

Trim—removes unwanted or "extra" sound from the beginning and end of an audio track.

Transcription toolbar—Contains the tools that let you speed up or slow down audio tracks.

Selection toolbar—this is located at the bottom of the Audacity main window, just below the project window. Its most common use is to set the Project Rate.