Grey noise

Shaped so every frequency sounds equally loud, rather than measuring equally loud.

Grey noise Generated live in your browser

Tap a second sound to layer it — rain under brown noise, for instance.

What is grey noise?

Grey noise is the only colour defined by your ears rather than by mathematics. It applies the inverse of the equal-loudness contour — the curve describing how sensitive human hearing is at each frequency — so that the result is perceived as flat. In practice that means boosted lows and highs with a dip through the mid-range, which is where your hearing is sharpest. White noise measures flat; grey noise sounds flat.

This page is a grey noise generator: the sound is computed in your browser rather than streamed from a file, so it starts instantly and never reaches a loop point. More on how that works.

Good for

  • People who want even masking across the whole range as the ear hears it
  • Anyone who finds white noise mid-heavy and brown noise too dark
  • Tinnitus masking, where even coverage is sometimes preferred

The details

Spectrum
Inverse equal-loudness contour — no fixed slope
Perceived as
Equally loud at every frequency
Sounds like
White noise with the harsh middle taken out
Depends on
Which loudness curve is used, so implementations differ

Questions

What is the difference between grey noise and white noise?

White noise is flat when you measure it with an instrument. Grey noise is flat when you listen to it. Because human hearing is far more sensitive around 2 to 5 kHz than at the extremes, flat-measuring white noise sounds mid-heavy and bright. Grey noise compensates by lifting the bass and treble and dipping the middle, so no part of the spectrum stands out.

Is grey noise good for tinnitus?

It is sometimes recommended for masking because it spreads perceived loudness evenly rather than concentrating it. Whether that helps depends entirely on the individual and on the pitch of their tinnitus, and masking is only one part of how tinnitus is managed. This is worth discussing with an audiologist rather than settling with a web page.

Why do different sites' grey noise sound different?

Because there is more than one equal-loudness curve, and they are defined at particular listening levels. A implementation based on one standard at one level will differ audibly from another. Unlike white or pink noise, there is no single correct grey.

Every colour of noise

Beyond the colours

Not noise colours in the strict sense, but built from them — and useful for the same reason.