Is your refrigerator running? No, this isn’t a poorly-delivered April fools joke. Your fridge is one of many real-world examples of noise right in your own home. But why are there so many kinds of noise, and how do you differentiate between them? Continue reading to learn about the wonderful world of noise!
What is Noise?
Noise is most commonly defined as “a sound, especially one that is loud or unpleasant or that causes a disturbance,” but not all noises are harmful. When we think of noise, our minds immediately flood with thoughts of construction sites, dogs barking, cars honking – the list goes on. However, many people are unaware of the different applications of noise in our daily lives, especially in music and audio.
What Are the Uses for Noise?
Noise gets a bad rap, but it truly has some practical applications. A spritz of noise on a synth patch can add brightness and offer an energetic boost. It can fill up frequencies in music and make a track come alive. Noise can also help cover up unwanted sounds and frequencies in a rough mix. Field recordings and ambient sounds help us sleep better and focus longer, and modern medicine has even been known to use noise to heal and treat ailments like Tinnitus.
Main Types of Noise
The noise variant that most people are familiar with is White Noise. It is the sound you hear when you accidentally switch to the wrong radio station or television channel. Technically speaking, White Noise is every frequency that’s audible to the human ear (20Hz to 20kHz) jumbled up into a harsh cacophony of sounds that constantly playback, all at the same rate.
As you venture deeper into the world of noise, you’ll stumble upon none other than Pink Noise. Sounds like the running of a fan, the calming flow of a river, or the rush of traffic are all examples of the Pink Noise that constantly surrounds us. Pink Noise is often mistaken for White Noise, but they differ vastly. Because we hear in octaves, Pink Noise is much more tolerable because every octave has equal power – rather than every frequency.
Brown Noise is quite similar to Pink, but with a few differences that set it apart. Named after Brownian Motion, or the random movement of particles in liquid, Brown Noise is essentially a more profound and bass-heavy version of Pink Noise, focusing on the lower end of the frequency spectrum. The most common examples of Brown Noise are ocean waves, thunderstorms, and waterfalls.
Blue Noise is the fraternal twin to Brown Noise, focusing on the high-end of the frequency spectrum. One of the most common examples you will hear of for Blue Noise is the hissing spray of a water hose. Blue Noise has very few low-frequency signals and very consistent energy. Because of this, this noise variant is excellent for Dithering, otherwise known as the process of minimizing audio distortions in music and audio applications.
Uncommon Types of Noise
Several noise variants aren’t talked about as often. These include Violet, which is similar to an open water faucet. Red, a very deep version of Brown Noise. Green, which is most commonly natural, non-man-made sounds that fall into the middle of the spectrum. Grey, an almost “3D” version of White Noise that is equally balanced amongst the spectrum. And Black Noise which is essentially silence, but with a tiny bit of random noise sprinkled throughout.
Noise isn’t just when your neighbors are throwing a party or when you use the garbage disposal. It surrounds us daily and often to our benefit, so choose wisely next time you use noise in your music production!