# What is brown noise?

https://hushmachine.com/sounds/brown-noise · Free; −6 dB per octave · Kallos Labs

> Brown noise is random sound whose power falls by 6 dB with each octave, so the low frequencies dominate. It sounds deep and rumbling, like a waterfall, heavy rain on a roof or a strong wind. The name comes from Brownian motion, not the colour.

## What it sounds like

Deep and low, like a waterfall or a strong wind. Also called red noise.

## How Hush Machine makes it

Hush Machine makes brown noise by running live white noise through a leaky integrator, which gives the 6 dB per octave fall. The app's tests measure the slope.

## How people use it

- A deep, steady background for focus, popular with people who find white noise too sharp.
- Covering low sounds such as traffic rumble or a neighbour's music.
- Sleep: many people prefer the darker sound at night.

## Questions

### Why is it called brown noise?

After Robert Brown and Brownian motion: the random walk of a particle produces this spectrum. It is also called red noise.

### What is the difference between brown and pink noise?

Brown noise falls twice as fast, 6 dB per octave against 3, so it sounds lower and darker than pink noise.

### Is brown noise good for focus?

Many people say a deep, steady sound helps them concentrate, and it is a popular choice for work. Research on noise and attention is mixed, and it differs from person to person, so try it and see.