What is pink noise?
Pink noise is random sound whose power falls by 3 dB with each octave, so every octave carries the same energy. To the ear it sounds more even and softer than white noise, like steady rain or wind in leaves.
Free−3 dB per octave
Coming soon to iPhone
What it sounds like
Softer than white, like steady rain.
How Hush Machine makes it
Hush Machine filters live white noise so its power drops by 3 dB per octave (a Voss-McCartney or Paul Kellet filter, as the app plan sets out). The app's tests measure the slope to within 1 dB per octave.
How people use it
- A balanced background for reading, work or sleep when white noise is too sharp.
- Room and speaker measurement: audio engineers use pink noise because each octave has equal energy.
- Layering under rain or a stream.
Questions
- Why is it called pink?
- By analogy with light: shifting white light's energy towards the low (red) end makes it look pinkish, and pink noise shifts sound's energy towards the low end in the same way.
- Is pink noise better than white noise?
- Neither is better; they sound different. Pink noise sounds softer and fuller, white noise brighter. Many people pick pink because white sounds harsh to them.
- What is 1/f noise?
- Another name for pink noise: its power is proportional to 1 divided by the frequency.