You've probably heard the term "white noise" used to describe any kind of background sound. But did you know that noise actually comes in colors—and each color has distinct characteristics that make it better suited for different purposes?
Understanding the difference between white, pink, and brown noise can help you choose the right sound for sleep, focus, relaxation, or masking distracting sounds. Let's break down what makes each one unique.
Why Are There "Colors" of Noise?
The naming convention comes from an analogy to light. Just as white light contains all visible colors at equal intensity, white noise contains all audible sound frequencies at equal intensity. Other noise "colors" are named based on how their energy is distributed across the frequency spectrum—with some loose comparisons to how those distributions would look if applied to light.
The key difference between noise colors is how the energy (or power) is distributed across different frequencies. This distribution is what gives each type of noise its characteristic sound.
White Noise: The Equal Opportunity Sound
What it is: White noise contains all frequencies in the audible spectrum (roughly 20 Hz to 20,000 Hz) at equal power. Every frequency gets the same amount of energy.
What it sounds like: Static from an old television or radio. A constant hiss. The sound of air escaping from a tire.
The catch: Even though white noise has equal energy at all frequencies, it doesn't sound balanced to human ears. Our hearing is more sensitive to higher frequencies, so white noise can seem "hissy" or harsh—like the treble is turned up too high.
Best for:
- Masking a wide range of environmental sounds
- People who need strong sound coverage
- Tinnitus relief (for some people)
- Creating a consistent audio backdrop
Common examples: TV static, fan sounds, air conditioners, radio static between stations.
Pink Noise: The Natural Balance
What it is: Pink noise also contains all audible frequencies, but the energy decreases as frequency increases. Specifically, the power drops by about 3 decibels per octave as you go up the frequency scale. This is sometimes called "1/f noise" because power is inversely proportional to frequency.
What it sounds like: Steady rainfall. A waterfall. Wind rustling through leaves. It sounds "fuller" and more balanced than white noise.
Why it sounds different: Because pink noise has less energy at higher frequencies, it sounds more natural to human ears. Our perception of loudness follows a similar pattern to pink noise's energy distribution, so it tends to sound like all frequencies are at the same volume—even though they're not.
Best for:
- Sleep enhancement (research shows it may boost deep sleep)
- Extended listening without fatigue
- Memory and cognitive benefits during sleep
- People who find white noise too harsh
Common examples: Moderate rain, ocean waves (without the crashing), rustling leaves, a gentle waterfall.
Brown Noise: The Deep Rumble
What it is: Brown noise (also called Brownian noise or red noise) takes the low-frequency emphasis even further. The energy drops by about 6 decibels per octave—twice the rate of pink noise. This means much more energy in the bass frequencies and very little in the highs.
Important note: The name comes from Robert Brown, who discovered Brownian motion (the random movement of particles in a fluid), not from the color brown. Some people call it "red noise" to maintain the color analogy.
What it sounds like: Distant thunder. A strong wind. A low rumble like being inside an airplane. Ocean waves during a storm. It's deep, rich, and enveloping.
Best for:
- Focus and concentration (especially for people with ADHD)
- Creating a "sound blanket" that feels immersive
- Masking low-frequency sounds like traffic or HVAC
- People who prefer bass-heavy, warm sounds
- Relaxation and stress reduction
Common examples: Rolling thunder, a strong river current, wind in a tunnel, the drone of an airplane cabin.
Comparing the Three
| Feature | White Noise | Pink Noise | Brown Noise |
|---|---|---|---|
| Frequency distribution | Equal at all frequencies | Energy decreases 3 dB/octave | Energy decreases 6 dB/octave |
| Sound character | Hissy, bright, static-like | Balanced, natural, full | Deep, rumbling, bass-heavy |
| Best for sleep | Some people | Many people | Some people |
| Best for focus | Some people | Some people | Many ADHD reports |
| Common complaint | Can sound harsh | — | May be too "heavy" |
Which One Should You Choose?
The honest answer is: it depends on your brain and your goals. Here are some guidelines:
Try pink noise first if:
- You want to improve sleep quality
- You're looking for something that sounds natural
- White noise sounds too harsh to you
- You want potential memory benefits
Try brown noise first if:
- You have ADHD or difficulty focusing
- You like deep, bass-heavy sounds
- You want to feel "wrapped" in sound
- Low-frequency noises (traffic, HVAC) are your main distraction
Try white noise first if:
- You need to mask a wide variety of sounds
- You have tinnitus
- High-pitched sounds are your main distraction
- You already know you like the sound of static or fans
The real answer: Experiment. Your personal preference matters more than any general guideline. What works for your coworker or partner may not work for you, and that's completely normal given how individual our auditory systems and preferences are.
The Quality Factor
Regardless of which color you choose, quality matters. Many apps and YouTube videos use short audio loops that repeat every few seconds or minutes. Over time, your brain may detect these repetition points, creating subtle distractions.
The best approach is real-time algorithmic generation—sound that's created mathematically in the moment rather than played back from a recording. This ensures truly continuous, seamless audio with no repetition artifacts.
Also, be mindful of compression. Heavily compressed audio files lose subtle frequency information, which can make the noise sound less natural and more fatiguing over time.
Finding Your Tonic
At the end of the day, the "best" noise color is the one that works for you. Some people are die-hard brown noise fans; others swear by pink. Some need pure white noise to mask specific sounds in their environment.
The beauty of sound therapy is that it's free, it's safe (at reasonable volumes), and it's endlessly customizable. Take the time to explore different options and find the one that helps your brain do what you need it to do—whether that's drifting off to sleep or powering through a difficult task.