|Whirlwind Intro to Audacity on Linux: From Recording to CD in One Lesson|
|Intro to Audacity: Page 2|
Audacity has nearly unlimited undo; still, it might be wise to make a backup copy of your original raw recording. I use the simple naming convention of projectname-orig-backup.
Now it's time to polish up your fab recording. Audacity has a very few functions that work during playback or recording, so always click Stop before you try to edit.
Start with deleting any sections of your new track that you don't want to keep — click and drag with the mouse cursor to select, then press the Delete key. All gone! What if you have deletion remorse and want it back? Audacity is forgiving and keeps a long Undo history, even between saves. It persists until you close Audacity. Press Ctrl+z or use Edit -> Undo to go back in time.
Audacity installs with a selection of special effects, and there is a whole world of special effect plugins for all occasions. On Debian and Debian-derivative distros try installing swh-plugins, tap-plugins, and invada-studio-plugins-ladspa. Fedora users check out the Planet CCRMA repos. The Plugins and Libraries page on Audacity.com has good information. Any Nyquist or Ladspa plugins should work on Linux, and installing third-party plugins or plugins you write yourself is easy — just copy them into /usr/share/audacity/.
Most times it is best to apply any effects before you make volume level corrections. I would love to go into detail on special effect plugins, but alas I am about to run out of paper. Don't be afraid to try them out; as long as you have backup copies of your original audio files you can go wild.
Next, adjust the volume. Maybe some parts are too loud in relation to the others, maybe some parts need a little boost. Use Effect -> Amplify for this. Enter an unsigned value like 3.0 in the Amplification box to raise the volume of your selection by three decibels, or a signed value like -3 to reduce the volume. (Of course you may use as many decibels as you want, and even fractions of decibels.) Never go over zero because this causes clipping, which creates distortion. Unlike analog audio, digital audio is unforgiving of distortion and it sounds pretty bad. There are good special effects for applying nice crunchy on-purpose distortion.
When your volume levels are all shipshape it's time to smooth out the intro and end, and any cuts in between, with fades. The easiest way to fade out or in is to select the part you want to fade, then click Effect -> Fade In or Fade Out. All you do is control the duration and the Fade effects do the rest.
Finally, apply normalization to bring the overall volume level up to the maximum. Select the whole track by double-clicking anywhere in the blue waveform, click Effect -> Normalize, check the "Remove any DC offset" box, check the "Normalize maximum amplitude to" box, set the value to zero, and click OK. (Figure 4.)
Exporting to CD-Quality WAV
Now we're in the homestretch. When your recording is all spiffed up and ready to be preserved for posterity on a CD, go to File -> Export. Choose the directory, give the file a name, and save it as a "WAV (Microsoft) signed 16-bit PCM" file (Figure 5). Then write this file to a CD using any CD-writing software you like, such as Brasero or K3B, and be sure to create a new audio project. Don't burn it as a data CD or it won't be a universal Red Book audio CD.
And that is your whirlwind introduction to the wonderful Audacity. Here some additional resources to help you get started:
- Book of Audacity, by me!
- Audacity documentation
- Audacity mailing lists
- Audio RecordingTerms Glossary