Noise may seem like an unwanted nuisance, but certain types of noise can actually have beneficial uses. Three types of noise that are often discussed are brown noise, white noise, and pink noise.
What is Noise?
In general, noise refers to unwanted, random sounds that interfere with another desired sound. It can be distracting, annoying, and make it harder to hear the sounds you want to hear.
However, not all noise is unwanted. Certain types of noise, when used intentionally and in moderation, can have positive effects. These include masking background sounds, promoting relaxation and sleep, and providing a comforting ambiance.
Types of Noise
The most common types of noise discussed are:
- Brown noise
- White noise
- Pink noise
These all refer to random noise spread across different frequencies. They are defined by the sound frequency distribution or power spectrum.
Brown noise refers to random noise that is louder at lower frequencies and softer at higher frequencies. The power decreases as the frequency increases, meaning there is more power concentrated at the lower end of the sound spectrum.
The name comes from Brownian motion, which describes the random, jittery movement of particles. This results in a sound reminiscent of a soft roar or rumble, like a rushing waterfall or strong wind.
Characteristics of Brown Noise
- Deeper, rumbling sound
- Focused at lower sound frequencies
- Mimics natural sounds like thunder, strong wind, or flowing water
- Volume decreases as frequency increases
Uses of Brown Noise
Brown noise has several beneficial uses and applications:
- Masking distracting sounds – The low rumbly sound can cover up noises that would otherwise be distracting, like voices, traffic, barking dogs.
- Promoting sleep – The low, deep, steady sound is relaxing. The consistent rumble blocks spikes and changes in ambient sound that could disrupt sleep.
- Tinnitus relief – The ambient noise may mask or distract from ringing or buzzing sounds in the ears.
- Concentration and focus – Providing a neutral auditory backdrop may help some people focus better than total silence.
- Relaxation – The subtle drone can have a calming, meditative effect.
Brown noise generators and audio are widely available online and in apps to provide these benefits.
White noise refers to random noise spread evenly across all audible sound frequencies. It is like static from analog TV or radio tuning into a channel with no transmission.
The defining characteristic is that the signal has equal power within a fixed bandwidth at any center frequency. All frequencies are represented evenly in white noise.
Characteristics of White Noise
- Neutral, constant hum
- All audio frequencies represented evenly
- Like the static sound from a detuned radio or TV
- Volume consistent across frequencies
Uses of White Noise
Like brown noise, white noise also has many uses:
- Masking sounds – The neutral hum can muffle distracting noises from indoors and outdoors.
- Better sleep – Blocks spikes in ambient sound and provides a calming backdrop for rest.
- Tinnitus relief – The ambient noise disguises ringing/buzzing sounds in the ears.
- Concentration – Provides an auditory backdrop that is less distracting than total silence.
- Relaxation and meditation aid – The steady hum can have a calming, meditative effect.
White noise is widely available through sound generators, fans, apps, youtube videos and other media.
Pink noise refers to random noise that is louder at lower frequencies and quieter at higher frequencies. However, the fall-off as frequency increases is less steep compared to brown noise.
While brown noise decreases at -6dB per octave, pink noise decreases at -3dB per octave. This means the higher frequencies are more prominent in pink noise compared to brown.
Characteristics of Pink Noise
- Warm, rounded quality
- Deeper than white noise, but not as deep as brown noise
- Volume decreases as frequency increases, but less steeply than brown noise
Uses of Pink Noise
Like brown and white noise, pink noise has applications in:
- Masking ambient sounds – Blocks distracting noises across a range of frequencies.
- Better sleep – Obscures spikes and changes in background sounds.
- Tinnitus relief – Can mask ringing or buzzing sounds.
- Focus and concentration – Steady backdrop that is less distracting than silence.
- Relaxation – Has a calming, soothing quality.
Some find the warm, rounded quality of pink noise to be the most pleasant and relaxing of the noise colors.
Comparing Noise Colors
While brown, white, and pink noise share similarities, understanding the distinctions between their frequencies can help choose the best one for specific needs:
|Noise Type||Sound Quality||Frequency Distribution|
|Brown Noise||Low rumble||Focused at lower frequencies|
|White Noise||Neutral hum||Equal power at all frequencies|
|Pink Noise||Warm, rounded||More power at lower frequencies, but less than brown noise|
So in summary:
- Brown noise is the deepest, with the most power in the bass frequencies.
- White noise has an evenly distributed power spectrum.
- Pink noise falls between brown and white – more bass presence than white noise, but not as much as brown.
Is One Noise Color Better?
There is no definitive “best” type of noise. The most suitable noise color depends on the specific application and individual preference.
Here are some general guidelines on choosing between them:
- Brown noise – Best for masking low rumbles like traffic or snoring; finding it most relaxing.
- White noise – Best for completely neutral backdrop; preferring a bright, consistent hum.
- Pink noise – Best for more balanced frequency coverage; finding the most natural, pleasant.
Try listening to samples of each noise color to see which you find most soothing, calming, and effective for your needs.
Brown, white, and pink noise describe different types of random noise frequencies. While noise may seem unwanted, these controlled noises can provide benefits:
- Masking distracting ambient sounds
- Promoting better sleep
- Providing tinnitus relief
- Helping focus and concentration
- Encouraging relaxation
Understanding the distinctions between the noise colors enables intentionally using them for specific needs and preferences. Ultimately there is no single best type of noise – finding the most suitable one depends on the application and individual tastes.