Even if you’ve never purposefully listened to white noise, or other color noises, you’re likely familiar with its sound. Whirring fans, humming refrigerators, staticky radios, pitter-pattering rain, roaring waterfalls—these are all forms of color noise, or what we call sound that is distributed with a continuous signal. Listening to color noises can improve sleep, increase focus, and enhance learning capacity.
Listen to the rainbow
Noise “colors” are distinguished from each other based on their spectral density—in essence, the way that the power contained by the noise signal is distributed over different frequencies. More simply, this refers to the variation in the location on the sound spectrum the noise’s energy concentrates, which subtly changes how the human ear perceives the signal.
- Pink noise has more energy concentrated at the lower end of the spectrum—so it sounds like white noise with a lower, deeper rumble. Much of what we think of as white noise (including the sound made by white noise machines and white noise soundtracks) is actually pink noise—it’s less grating to our ears and minds.
- Brown noise, short for Brownian noise and sometimes also called red noise, is a deeper sound more reminiscent of ocean waves.
- Green noise has a similar frequency to white noise but with sounds that are more like nature and less like TV static.
- Violet noise and grey noise also have variations of these traits. However, experts say that categorizing sound isn’t an exact science, so the differences between color noises aren’t firmly established and their sounds may overlap.
- White noise is a uniform mixture of all frequencies detectable by the human ear. Calling noise “white,” therefore, is a nod to the color spectrum, as white light emits all pigments of light at equal intensity.
Bringing the noise may have benefits
So, what happens when we listen to color noise? More research is needed to fully understand its impacts on our brains, but one scientific theory, called stochastic resonance, posits that white noise can help us tune out external stimuli and unhelpful internal chatter to focus on other stimuli more clearly.
Tune in with care
Experts agree that listening to color noise is completely safe as long as—like with all music—you don’t listen to it too loudly. Listening to anything above 70 decibels for a prolonged period can damage your hearing.
Start listening
If you’re intrigued by the concept of color noise, it’s easy to start bringing it into your life and identifying which shades you like best. Try plugging in a pink noise machine while you’re sleeping or putting on a brown noise track during your morning meditation or afternoon report-writing session (particularly if colleagues are talking loudly around your desk!).
Color noise also works while on the move: if you feel overwhelmed by the sounds of the city during your commute, listening to color noise in your headphones can be a great way to tune out and relax.
By Isabela Vera
