White noise

A special type of random noise where the energy content is the same at each frequency. Strictly speaking, true white noise would have energy extending from DC, or zero frequency. In practice, we see only band-limited white noise, e.g., the noise heard when an FM receiver is tuned between stations is quite close to white noise over the AFaudible frequency range. Because of the ears’ peculiar method of determining loudness of sounds, white noise sounds as if it has more energy at high frequencies than low. Also (imprecisely) called thermal noise and resistance noise. See pink noise, noise floor.