Brownian noise
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In science, Brownian noise (), also known as Brown noise or red noise, is the kind of signal noise produced by Brownian motion. The term "brown noise" comes not from the color, but in honor of Robert Brown, the discoverer of Brownian motion.
Explanation
The graphic representation of the sound signal mimics a Brownian pattern. Its spectral density is proportional to 1/f2, meaning it has more energy at lower frequencies, even more so than pink noise. It decreases in power by 6 dB per octave and, when heard, has a "damped" or "soft" quality compared to white and pink noise. See also purple noise, which is a 6 dB increase per octave.
Production
Brown noise can be produced by integrating white noise. That is, whereas (digital) white noise can be produced by randomly choosing each sample independently, brown noise can be produced by adding a random offset to each sample to obtain the next one.
