Pink Noise Vs White Noise Vs Brown Noise Differences (With Samples)

Curious to learn what the differences are for pink noise vs white noise vs brown noise? You’re in the right place!

I’ll explain it all here in a way anyone can understand – plus you can hear my noise examples for yourself.

Pink noise vs white noise vs brown noise differences

what is pink, white, brown noise infographic

Pink, white, and brown noise are what you call colored noise (sound patterns). The noise color name is used to describe the characteristic power spectrum of a noise signal.

In other words, colored noise signals have different output patterns (patterns of their volume level) for different frequencies as you’ll see below.

While there are others as well (violet noise, blue noise, grey noise, etc.) pink, white, and brown are some of the most common. The three covered in this article are some of the best for blocking ambient noise and they can help when used as sleep noise patterns.

What is pink noise?

pink noise example snapshot on real time analyzer

An example image of pink noise on a real-time analyzer (RTA). Here the volume is shown as even, representing how our ears perceive it.

Pink noise is a random sound pattern in which the spectral power density (the power per frequency) decreases as the frequency increases. In other words, the volume output is inversely proportional to the frequency of the signal.

It’s sometimes described as 1/f noise (1/frequency) and when plotted on a logarithmic scale will appear as a downward slope. However, pink noise sounds like it has an even volume to the human ear as we are more sensitive to upper sound frequency ranges.

What is white noise?

white noise example snapshot on real time analyzer

An example image of white noise on a real-time analyzer. Here the RTA shows how white noise is perceived by our ears – it sounds “louder” at higher ranges.

White noise is characterized by a random sound pattern that has a flat spectral density (the same volume amplitude or intensity) across all sound frequencies. In other words, it has equal intensity across the increasing frequency range.

To human hearing, it can sound like higher frequencies are louder since our ears are more sensitive to those.

What is brown noise?

brown noise example snapshot on real time analyzer

An example image of brown noise on a real-time analyzer. Here the RTA shows how brown noise is perceived by our ears – the lower frequencies have much higher volume output so you’ll hear more bass.

Brown noise (also called Brownian noise or red noise) is a random noise pattern that has a higher power intensity (higher volume output) at lower frequencies.

Human hearing is worse at lower frequencies so we tend to perceive bass less with white or pink noise. Because brown noise has a higher output at lower frequencies, it sounds “deeper” and your ears can hear the boosted bass tones.

Brown noise is similar in some ways to the sound of ocean waves.

Note: “White” noise is also commonly used as a name for sound patterns that are somewhat similar but not exactly the same. For example, a box fan or sound machine’s output may be called “white” even though it’s not technically correct.

White, pink, and brown audio samples

Here’s a sample of each sound you can try for yourself. Each video shows how the sound pattern appears on a test analyzer program, more closely representing how they appear to your ears.

(Note that when shown on a logarithmic engineering graph chart they’ll have a different shape due to being graphed by the octave bands – it can be a bit confusing.)

1. Pink noise sample

2. White noise sample

3. Brown noise sample

https://youtu.be/ZDf-aq_AqA4″

Marty

About the author

Marty is an experienced electrical, electronics, and embedded firmware design engineer passionate about audio and DIY. He worked professionally as an MECP-certified mobile installer for years before moving into the engineering field. Read more »

Leave a Comment