As much I want to root for Audacity for being an open source and multi-platform multitrack recording solution, it’s just not there yet. I set it up for my coworker to record lectures and, even in this light-duty (mono 44.1 recording, nothing fancy), after about 10 min of material the program starts to sputter and exhibit delays in responding. This is on a machine with a GB of RAM! Occasionally the project file becomes corrupted and, although you can open it, see the waveforms, and export, you can’t play the project anymore without a long crash. This happened this morning; I was able to export what was there, but skips and glitches made the track unusable. Even when the entire recording and mixdown does work, at every other edit point in the mixdown is an audible pop.

For all its instability, there are two very nice Audacity features that I’d love to see in Adobe Audition:

Visible RMS levels on the waveform.

This gives you a decent visual clue of how “loud” a track is across time. While RMS doesn’t equate to “loudness” (unless it uses a reverse equal-loudness contour), it’s mostly proportional to it if the overall frequencies stay the same (as with speech).

View results of volume-adjustment curves in real time

When you draw a curve you see the waveform change to the result of the curve as it will be applied, making it possible to truly dial in the exact volume change you want rather than repeatedly guessing and listening.

The above features allow you to quickly visually shape your desired loudness curve out of the existing wave. Speakers tend to gradually gain/lose volume over several minutes, so this makes compensating for that cake. These two alone make it worth keeping Audactiy around just for situations needing sharp leveling.