Audio or wave editing software represents a veritable Swiss army knife of tools, allowing audio enthusiasts to perform a variety of common tasks. These include general recording into your computer (from radio, vinyl, tapes, etc.), noise reduction to clean up your recordings, editing to cut up and manipulate the sound files, and processing to apply effects.
Here we go click-by-click through feature highlights of Audacity, a free and full version application that we’ve put on the November PC World cover CD. It supports all versions of Windows from 98 onwards, in addition to Linux/UNIX and Mac OS 9/X.
Audacity is a free cross-platform open-source audio editor supporting WAV, AIFF, MP3 and OGG files and VST plug-ins.
This column has previously referred to both the shareware audio editor Goldwave (www.goldwave.com)and the trial version of Cool Edit 2000 (www.syntrillium.com) in various tutorials. Unfortunately, the latter has recently been discontinued and its higher-specified sibling, Cool Edit Pro, sold to Adobe and renamed Adobe Audition. Interestingly, Sonic Foundry (www.sonicfoundry.com), developers of the highly popular Sound Forge audio editor as well as the ACID and Vegas audio-visual packages, has also sold off its desktop products, in this case to Sony Pictures Digital. Although these products’ continuing development is confirmed, change is certainly afoot. One mainstay remains Steinberg’s Wavelab (www.steinberg.net) which continues to rival Sound Forge in feature-set strength.
Although freeware can sometimes be a little rough around the edges, programs such as Audacity (http://audacity.sourceforge.net) -- which is in perpetual development -- are raising the standards of freeware and can also save you unwarranted expense. With this software, you can perform all the tasks described in the introduction. Effects such as bass boost, wahwah and noise removal are built in, and there’s also support for free VST plug-in effects. The ‘plug-ins’ link on the Audacity Web site has many links to the best commercial and free VST plug-ins.
File types and preferences
Audacity 1.0.0 supports importing (Project-Import Audio) and exporting in the common WAV (PC) and AIFF (Macintosh) formats. This can also be done with OGG (vorbis) and MP3 files, although for MP3 export support you’ll need to download a separate MP3 encoder from the Windows download section of the Audacity site. To export an opened file as a different format, simply select the appropriate Export as... option from the file menu. A file can also be saved as an ongoing Audacity project (File-Save Project). You’ll notice that when you open more than one file, each is displayed in individual windows that you can cut and paste between.
Of course, you’ll want to define the quality settings of these export formats and check the preferences for Audacity as a whole. Do this from File-Preferences or use
Waveforms and interface
The convention used in audio editors is that an opened audio file (waveform) when drawn on your screen begins on the left and ends on the right. If you’ve opened a stereo file, you’ll see two waveforms, the top representing the left channel, the bottom the right channel. To make them individually editable in Audacity, you’ll need to click on the down arrow to the left of the waveforms and select the Split Stereo track option. Underneath this down arrow, you’ll see Mute and Solo buttons. If you wanted to do multi-track recording and needed to add a new track on which to record (Project-New Audio Track), these would allow you to mute an individual track or have it play solo, respectively.
To record on a new track, click on it and then on the Record button at the top of Audacity. If you were recording tapes or vinyl into your computer, this is when you would press play on their devices also.
TIP: Don’t forget to make sure you have plenty of hard disk space if you’re going to be recording a lengthy piece.
Next to the record button, you will see a volume control, stop and play controls, and four icons on the left. The top left icon is your basic selection tool, allowing you to select certain parts of your waveform to edit. To the right of this is an envelope tool allowing you to draw over the waveform and effect things such as volume fades. The bottom left icon allows you to move a selected audio track from left to right -- useful for multi-tracking -- while the bottom right tool is a magnifying glass allowing you to zoom in (simply click on a waveform) and zoom out (press
Now that we’ve come to terms with the basic capabilities and controls of Audacity 1.0.0, next time we’ll use it to reduce the background noise and crackles of recordings, normalise volume levels, remove vocals for remixes, and edit MP3 tags, plus we’ll take a look at the new features in Audacity 1.2.0.