Sound waves can be represented by their two basic characteristics, pitch and volume. In electronic music, pitch is defined as frequency - the number of vibrations that occur each second (measured in Hertz - Hz). The volume of the sound is its amplitude. In the waveform graph, the amplitude is represented by the wave height. A complex tone consists of several sound waves. It will have a fundamental frequency and additional sidebands or overtones. The fundamental one is the wave with the lowest frequency or the highest amplitude and thus dominates the combination of tones. The overtones add color to the sound, giving it character or timbre. Most of the sounds we hear in electronic music are composed of many sound waves that are specially modified to create a sound color, it is however possible to catalog a few basic waveforms that serve as building blocks for an electronic music composer.
- Sine wave: This is the simplest type of wave. Theoretically, it should not contain any harmonics or overtones. Although the sound of a sine wave can be compared to the sound of a flute, even the flute has more substance and depth than a pure sine tone. The sine is a thin, precise tone, similar to a whistle.
- Triangle wave: A triangular wave is similar to a sine wave, but contains harmonics or side bands. Its sound has more substance and depth than a sine wave, resembling the sound of a flute or a trumpet.
- Sawtooth wave: This wave has a sharp, angular shape, like the saw teeth. It has twice as many harmonics as a sine wave. It has a full, humming sound, like a reed instrument such as saxophone.
- Pulse wave: This wave has the same number of overtones as a triangle wave but has the roughness and crackling sound of a sawtooth wave. The waveform jumps instantly from the lowest point to the highest. When plotted, it consists of only right angles and is often called a square wave or a rectangular wave. A pulse wave has a sound similar to the combined sounds of a flute and an oboe. It can also be used to create sharp rhythmic sounds more easily than other basic waveforms.
- White noise: It does not show the structural symmetry of sine, triangular, sawtooth or pulse waves. White noise is to these four fundamental waves what gray is to the primary colors: it is an amalgamation of all of them, without any dominant element. White noise is created when all the frequencies and amplitudes of the sound occur randomly in the audio spectrum. It can be filtered and refined to sound like the wind or the ocean and is a rich sound source for an electronic music composer.
Pink noise is a distilled form of white noise, it contains all frequencies from 18 Hz to 10,000 Hz. At the other end of the audio spectrum, noise limited to the frequency range from 10,000 Hz to 22,000 Hz is blue noise.