Some people like to work in the cafe, but not in quiet library - some studies show that coffee shop environment will be more conducive to the sound focus, enhance creativity at work, this environment can be considered a kind of sound. " white noise. " If you like listening to the rain, do not miss this application. In addition to sound variety, also supports a variety of sound reverberation, and other custom scene. Writing, running, travel time can be opened to listen! It contains a variety of natural ambient sound. Imitate the sounds of nature - this is the white noise (white noise), improve concentration, relaxation, fine. Refers to white noise in a wide frequency range, the energy of each frequency band included in the noise and other noise equivalent bandwidth. Usually physically translate it into white noise (white noise). White noise or white noise is a constant power spectral density of random signals or random process. In other words, the signal power in each band is the same, since the white light is a mixture of various frequencies (colors) of monochromatic light, so that this signal has the nature of a flat power spectrum is called "white", this signal has therefore been called white noise. Noise signal relative, other do not have this property are called colored noise. Ideal white noise has infinite bandwidth, so its energy is infinite, which is impossible in the real world exists. In fact, we often limited bandwidth of the signal level regarded as white noise, because it makes us more convenient in mathematical analysis. However, the white noise in the mathematical treatment is more convenient, so it is a powerful tool for system analysis. In general, as long as the spectral width of a noise process has the effect that it is much larger than the bandwidth of the system, and its spectral density can basically be considered as a constant in the bandwidth, you can use it as white noise to deal with. For example, thermal noise and shot noise over a wide frequency range with a uniform power spectral density can usually think they are white noise. When you need to concentrate on work, there is always a complex and surrounding sound, you can use these two sounds to be obscured. In general, under normal circumstances you can use the white noise, pink noise is specifically for voice masking material. Pink noise has been known frequency is inversely proportional to (1 / f) noise, because its energy is inversely proportional to the frequency distribution, or every octave (Octave) the energy recession 3dB. One application is the white noise of architectural acoustics, in order to weaken the internal space distracting and do not want the noise (such as conversation human) appears, use continuous low-intensity noise as background sound. Some sirens of emergency vehicles also use white noise as white noise to pass through cities such as background noise and traffic noise does not cause reflections, it is easier to attract attention. In electronic music also applied white noise, which is directly or as the input signal of the filter to produce other types of noise signals, especially in audio synthesis, often like cymbals for reproducing a high frequency domain so that percussion noise components. White noise is used to generate the impulse response. In order to ensure a balanced effect Venue concerts or other performances, it issued a white noise or pink noise from the PA system instantly, and in a different place to monitor the noise signal, so that engineers can effect a building acoustics can automatically enlarge or cut certain frequencies, which can be adjusted to give effect overall balance a balanced harmony. White noise can be used for frequency response of the filter amplifier or electronic test, sometimes it is used with a flat response microphone or automatic equalizer.