An OscillatorNode generates a periodic waveform at a given frequency. The waveform shape determines the harmonic content — and therefore the timbre you hear.
Select a waveform and adjust frequency and volume. The oscilloscope shows the actual audio signal in real time.
Each shape has a characteristic harmonic series. A sine is a single pure frequency. Square, sawtooth, and triangle are built from infinite sums of sine waves — their brightness comes from upper harmonics.
Single harmonic (fundamental only). Pure, smooth tone. Used for sub-bass and mellow lead sounds.
Odd harmonics only (1, 3, 5…). Hollow, nasal sound — similar to a clarinet's timbre.
All harmonics (1, 2, 3…) at decreasing amplitude. Bright, buzzy — the classic synth lead.
Odd harmonics only, falling off faster than square. Softer than square, brighter than sine.