White noise machine

A white noise machine is a device that produces a sound that is random in character, which sounds like a rushing waterfall or wind blowing through trees. Often such devices do not produce actual white noise, which has a harsh sound, but more often pink noise, whose power rolls off at higher frequencies, or other colors of noise.

Use

White noise devices are available from numerous manufacturers in many forms, for a variety of different uses, including audio testing equipment, sound masking products, sleep-aid devices, and power-nap machines. Sleep-aid and nap-machine products may also produce other soothing sounds, such as music, rain, wind, highway traffic and ocean waves mixed with—or modulated by—white noise. White noise generators are often used by sufferers of tinnitus to mask their symptoms.

Sound and noise have their own measurement and color coding technique, which enables specialized users to identify noise and sound according to respective needs and utilization. These specialized needs are dependent on professions and particular needs, as different needs are required by varied activities such as a psychiatrist who needs certain sounds for therapies and treatments on a mental level, and patients who suffer from certain conditions ranging from insomnia to anxiety and even tinnitus, these conditions are overcome with special devices which are designed to create certain sounds that overcome such conditions at a mental level. This device is known as a white noise machine, where “white” is the color code given to noise having a particular frequency spectrum.

White noise

In signal processing, white noise is a random signal with a constant power spectral density. The term is used, with this or similar meanings, in many scientific and technical disciplines, including physics, acoustic engineering, telecommunications, statistical forecasting, and many more. White noise refers to a statistical model for signals and signal sources, rather than to any specific signal.

In discrete time, white noise is a discrete signal whose samples are regarded as a sequence of serially uncorrelated random variables with zero mean and finite variance; a single realization of white noise is a random shock. Depending on the context, one may also require that the samples be independent and have the same probability distribution (in other words i.i.d is a simplest representative of the white noise). In particular, if each sample has a normal distribution with zero mean, the signal is said to be Gaussian white noise.

The samples of a white noise signal may be sequential in time, or arranged along one or more spatial dimensions. In digital image processing, the pixels of a white noise image are typically arranged in a rectangular grid, and are assumed to be independent random variables with uniform probability distribution over some interval. The concept can be defined also for signals spread over more complicated domains, such as a sphere or a torus.

White noise (disambiguation)

White noise is a signal or sound with a flat frequency spectrum.

White noise may also refer to:

In music

White

White is an achromatic color, literally a "color without hue", that is a mixture of the frequencies of all the colors of the visible spectrum. It is one of the most common colors in nature, the color of sunlight, snow, milk, chalk, limestone and other common minerals. In many cultures white represents or signifies purity, innocence, and light, and is the symbolic opposite of black, or darkness. According to surveys in Europe and the United States, white is the color most often associated with perfection, the good, honesty, cleanliness, the beginning, the new, neutrality, and exactitude.

In ancient Egypt and ancient Rome, priestesses wore white as a symbol of purity, and Romans wore a white toga as a symbol of citizenship. In the Middle Ages and Renaissance a white unicorn symbolized chastity, and a white lamb sacrifice and purity; the widows of kings dressed in white rather than black as the color of mourning. It sometimes symbolizes royalty; it was the color of the French kings (black being the color of the queens) and of the monarchist movement after the French Revolution as well as of the movement called the White Russians (not to be confounded with Belarus, literally "White Russia") who fought the Bolsheviks during the Russian Civil War (1917-1922). Greek and Roman temples were faced with white marble, and beginning in the 18th century, with the advent of neoclassical architecture, white became the most common color of new churches, capitols and other government buildings, especially in the United States of America. It was also widely used in 20th century modern architecture as a symbol of modernity, simplicity and strength.

Noise

Noise is a variety of sound. It means any unwanted sound. Sounds, particularly loud ones, that disturb people or make it difficult to hear wanted sounds, are noise. For example, conversations of other people may be called noise by people not involved in any of them; any unwanted sound such as neighbours playing loud music, portable mechanical saws, road traffic sounds, or a distant aircraft in quiet countryside, is called noise.

Acoustic noise can be anything from quiet but annoying to loud and harmful. At one extreme users of public transport sometimes complain about the faint and tinny sounds emanating from the headphones or earbuds of somebody listening to a portable audio player; at the other the sound of very loud music, a jet engine at close quarters, etc. can cause irreversible hearing damage. At intermediate levels there are a range of deleterious health effects from noise. This "intolerable corruption of human space" can be called noise pollution. A claim made by Luigi Russolo in his article, The Joys of Noise is that noise has become so prominent that pure sound no longer exists.