11 - Make Some Noise

Let’s expand a bit on our sound generating toolkit, and produce 30 seconds of white noise. Go back to Generate in the top menu, click on Noise..., set the amplitude to 0.2 to avoid damaging your ears and click OK. Zoom in by clicking on the magnifying-glass button and clicking on the generated waveform a few times. The result should look like this:

You will notice that it sounds pretty uncomfortable. This is because white noise has the same amplitude in all the frequency bands, but as we remember from the loudness section, we are much more sensitive to higher frequencies, and therefore white noise is not very nice when played back at high levels. It is usually better to use pink noise, a kind of noise with less high frequency content than white. In Audacity you can do this easily by going to Generate -> Noise... and select Pink from the Noise type: dropdown menu.

The resulting waveform looks something like this:

… and sounds a lot more pleasant than white noise.