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• Audacity
• Audacity
• Installing Audacity and LAME MP3 Encoder
• Noise Reduction
• Using the Fade Effect
• Exporting MP3s

Investigate Educational Technologies :: Complimentary Tools

Audacity

Instructors may want to edit pre-existing sound clips of various kinds: music, documentary or film soundtracks, historical media, and primary research audio. Perhaps a historian might want to use a short clip of a presidential address, a linguist a sample of dialect from a media source, a media studies professor a clip from a film or an advertisement.

This tutorial explains how to use some of the more important functions of Audacity such as reducing background noise from your sound files for better audibility, adding fades and other effects to your audio, and exporting your end product as an MP3 file (which is much smaller than a WAV or other audio file type).

Installing Audacity and LAME MP3 Encoder

To download Audacity, go to: http://audacity.sourceforge.net/download/.

Under Recommended Download, select your operation system (for example, for Windows choose: Audacity 1.2.4b installer .exe file, 2.5 MB).

Select a mirror from which to download Audacity. Save the file to the location of your choice, such as your desktop.

Find the audacity-win EXE file you just downloaded and run it. This will start the installation program. Go through the process and install Audacity in the location of your choice.

To export an Audacity audio file in the widely used MP3 format you will need to:

• Download an encoder file
• Place it in a folder on your local computer
• Locate the encoder file with the Audacity software

Under Optional Downloads, select LAME MP3 encoder.

Under your operating system, select the LAME download page. Select a mirror from which to download the encoder file, lame_enc.dll.

Using WinZip, or some other decompression program, unzip the downloaded file to the directory of your choice (you can put it into the Audacity directory, or create a new directory). The important thing is to remember where you put it so that later, when you want to export your file to the MP3 format, you can point Audacity to the lame_enc.dll file. For help with installing the LAME MP3 encoder, see: http://audacity.sourceforge.net/help/faq?s=install&i=lame-mp3.

Before you move on to the next section, you may find it helpful to review some Tutorials from the Audacity web site. The Audacity help page explains basic tasks like cutting, pasting, or making a selection.

Noise Reduction

When you're recording sound, you may find that extraneous background noise (e.g., air conditioner noise, the hum of a fan, or the whirring of your computer) ends up in your sound file, compromising its quality.  Audacity makes it easy for you to select and remove these kinds of "white" noise, giving you a cleaner final product. However, you should be aware that Audacity isn't designed to remove irregular noises (like people talking), so you should try to avoid those kinds of noises by choosing someplace quiet to do your recording.

To hear an example of noise reduction, listen to these audio clips:
Sound clip before noise reduction
Sound clip after noise reduction

Open an existing audio file, or record new audio.

Select a portion of the audio that is ONLY background sound.

Go to Effect > Noise Removal... and click Get Noise Profile. This tells Audacity what to search for and remove.

Now select your entire audio track, or the portion on which you want to reduce the noise, and go to Effect > Noise Removal... again. This time, choose how much noise you want removed, and click Remove Noise.

To listen to the sound clip you just edited, click the Play button.

Using the Fade Effect

Open an existing audio file in Audacity, or record new audio.

Select the portion of audio you wish to fade.

Go to Effect > Fade In (or Fade Out).

The audio you selected has been faded. You can click the Play button to listen to the clip you've just faded.

Exporting MP3s

Once your project is ready to be exported, go to File > Export as MP3... and choose a location for the file.

Audacity will ask you if you would like to locate lame_enc.dll; click Yes.

Go to the folder you created for LAME. The necessary file will be in that folder.

If you want, you can edit the ID3 tags. Many media players read the ID3 tags and will display the information in them while the file is playing. When you are finished click OK.