- Tech know how online

pink noise

Noise is statistical level and phase fluctuations. In engineering, one influences the distribution of noise with respect to the frequency distribution.

While white noise has a constant spectral energy over all frequency ranges, pink noise has an energy density that decreases with frequency and is inversely proportional to frequency (1/f) at 3 dB per octave. Relative to an octave, the noise energy is constant, thus pink noise decreases with higher frequencies. Therefore, pink noise is also referred to as 1/f noise.

This means that each octave always has the same energy density. For example, the frequency range from 1 kHz to 2 kHz has the same noise density as the frequency range from 2 kHz to 4 kHz or that from 5.5 kHz to 11 kHz.

Noise types and their frequency energy density

Noise types and their frequency energy density

Thus, the energy density drops by 3 dB or by a factor of 0.7 when the frequency is doubled. Pink noise can be generated by passing white noise through a filter with a slope of 3 dB/octave.

In acoustics, pink noise is used for acoustic backgrounds and also serves as a modulation signal in synthesizers. In addition, it is used in acoustic measurement technology, for example in the measurement of critical frequency bands.

Englisch: pink noise
Updated at: 23.09.2015
#Words: 196
Links: level, phase, indium (In), noise (N), frequency (f)
Translations: DE

All rights reserved DATACOM Buchverlag GmbH © 2022