Blue noise generator
The mirror image of brown: energy climbs as frequency rises, so almost everything you hear is at the top. Useful, briefly, and not for eight hours.
Blue noise gains 3 dB per octave as frequency rises — the exact opposite tilt to pink. The result is a bright, airy hiss with almost no body. It is a real and useful signal in audio engineering and image processing, and it is the least comfortable of the colours to listen to for long.
What it is genuinely used for
| Field | Use |
|---|---|
| Audio engineering | Dithering — the noise added when reducing bit depth, because pushing it upward hides it where the ear is less sensitive |
| Image processing | Blue-noise dither patterns, which look less structured than ordered ones |
| Hearing checks | Quickly revealing whether a system reproduces the top octave at all |
| Masking | Only narrowly — it covers hiss and sibilance, and nothing below that |
Why it is a poor sleep or focus bed
Everything a masking bed is asked to cover — traffic, voices, footsteps, plumbing — sits below the range where blue noise has its energy. So it fails at the job while being the most fatiguing colour to hear. For sleep use pink or brown; for voices use white.
This page exists because the colour is part of the set and people look it up, not because we recommend it. Keep the volume low and the session short.
Questions
What is blue noise used for?
Mostly technical work: dithering in audio and image processing. As a listening bed it is a niche choice at best.
Is blue noise the same as violet noise?
No, but they are neighbours. Violet rises at 6 dB per octave — twice the tilt — and is brighter still.
Can I sleep to blue noise?
You can, but almost nobody wants to. It masks the wrong part of the spectrum and is tiring.
Running this on a phone? The Brainwave Generator app keeps playing with the screen off, works without a connection, and carries the same engine. Free on iOS and Android.