Some sounds help us fall asleep, some wake us up, some irritate us, while some others anger us, and this is because sounds have energies, and this energy depends on the sound’s frequency, amplitude and dimension. And on the basis of this energy, sounds have now been categorized into colours. Audio researchers call this the rainbow of sounds.
After 20 years of research, scientists have been able to determine that white, brown, and pink sounds calm people, provide mental peace, and develop focus. Many companies in the USA are developing devices based on white sounds, which will help fall asleep. White-sound based devices are also being made to help babies in the womb fall asleep. Slow sounds emanating out of air-conditioners and fans have been labeled as white sounds, and when the intensity of such sounds increases, they come into the category of pink sounds. The sounds which can be heard clearly without any difficulty are brown sounds. One example of brown sounds are the sounds of conversation in a peaceful environment.
Scientists researching on sounds have said that brown sounds are really close to white and pink sounds. On the other hand, purple sounds are those which trouble a person, like the sounds of shouting and screaming or sobbing.