Also, triangular wave. An audio waveform theoretically comprised of an infinite set of odd harmonic sine waves. It is often used in sound synthesis where its timbre is less harsh than the square wave ...

The linearity of triangular waveforms makes the triangular-wave generator useful in sweep circuits and test equipment. For example, switched-mode power supplies and induction motor-control circuits ...

First p-jfet – waveform is the output taken across R1. Input is a 1kHz triangle wave, set to oscillate between -3V and +3V. Bumping these up to ±3.1V or down to ±2.9V made the waveform look less nice.