Timbre and Noise
Timbre & Noise. Beyond amplitude (loudness) and frequency (pitch), there is another, more elusive characteristic of sound known as timbre. Timbre, or tone color, is the quality of a sound that distinguishes it from others, even when pitch and loudness are identical. It is shaped by factors like harmonics, the sound's envelope (attack, decay, sustain, release), and its spectral content. Timbre is often perceived as the quality or texture of a sound, influenced by its spectral content or overtones, as well as its durational features, such as the sound's envelope (attack and decay).
Another factor affecting timbre is noise—those unpredictable, aperiodic fluctuations within a sound. Noise is characterized by a broad range of frequencies without a clear pitch and includes types like white noise (evenly distributed frequencies), pink noise (equal energy per octave), and brown noise (more low-frequency energy). In computer music, understanding timbre allows for the creation and differentiation of unique sounds, while noise can be used for texture, sound masking, or experimental purposes. In 1913, Italian Futurist composer Luigi Russolo famously explored the concept of noise in his manifesto, The Art of Noises.
