What are white, pink and brown noise?

That’s right, sound now comes in all the colours of Neapolitan ice cream. And, if you want to sample them you can just plug their names into YouTube or Spotify, but understanding the difference takes a bit more brain power.

You need to think in terms of frequencies – the differences in pitch that give us musical notes. While white noise contains all the frequencies mashed together equally, brown and pink noise put more energy into the lower frequencies, the result being a bassier sound. Brown noise is the bassiest and, according to some, the most soothing. Listening to it feels a bit like being awake on an aeroplane at night.

As for whether it’s ‘better’, well, brown noise is the most on-trend noise colour, with TikTok users, especially those in the ADHD community, singing its praises. Many claim brown noise helps them to focus. Others use it in preference to white noise as a sleep aid. The reality is that scientists don’t really know whether any of these noises work for the purposes that we’re using them for, or whether they’re safe in the long term.

Outcomes from sleep studies on white and pink noise vary wildly, a 2021 review article by University of Pennsylvania researchers found, with some research suggesting that playing continuous noise actually disrupts sleep rather than improving it.

Claims about brown noise are even flakier since we hardly have any evidence. That doesn’t mean it doesn’t work though – we just don’t know yet – but certainly the sounds that work for one person might not work for another.

Still, having answered your question while listening to brown noise, I can personally attest to its soothing qualities!

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Asked by: Anne-Marie Ferguson, via email

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