For the purpose of this experiment we'll need to work on a very small waveform of only a few cycles in length. Far too short a time period for anyone to hear it, so the sample must be played on a loop. You can do this by clicking on the button indicated below in the control window.
This will open up the window displayed below. Set it as pictured and it'll loop away on playback with the yellow playback button.
Creating a Waveform
Now that we've ensured we'll be able to appreciate any waveform we've created, let's make a waveform. To do this, we will need to use the expression evaluator. You can find it in the menu pictured below.
Once in it, you can just put an equation into the expression field and make a wave based on that, but you can also choose from a list of presets that will generate a formula for you. For our purposes we want a sine wave at 500Hz. Clicking on it in the presets will give us the result below.
With that entered, click OK and the waveform will be generated. The resultant wave is pictured below
The expression evaluator can be used to add multiple harmonics of a wave. The values entered into the expression field in the below screenshot add the 3rd, 5th, 7th and 9th harmonics to the same sine wave we created before.
The resultant waveform is pictured below.
What was a collection of sine waves is starting to strongly resemble a square wave.
The wave's shape differs depending on the harmonics used. This next wave form is built up from the 2nd, 3rd, 4th and 5th harmonics of the original 500Hz sine wave.
The result strong resembles a sawtooth waveform.
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