Whats the difference between Pink Noise and White Noise?
There are two popular types of broadband test signals that are used for spectrum analysis: pink noise and white noise. White noise sounds like the noise you hear when you dial between stations on the radio. Its also commonly referred to as “hiss”. White noise has equal amounts of energy for any given linear frequency band. There is as much energy in the range from 0 to 1 kHz as from 1 kHz to 2 kHz. When you look at white noise using an FFT analyzer you see a flat frequency response. That is, all frequencies appear at the same loudness across the spectrum. But if you view white noise with an RTA, the RTA shows the noise much more like our ears hear it. To our ears the white noise is hissy sounding with an emphasis on high frequencies and a lack of low frequencies. That is also how white noise appears on a RTA where it exhibits a 3 dB per octave rise with frequency. Pink noise has equal energy per octave or fractional octave band. This means that a 1 octave wide band of pink noise center
