Cover What is pink noise, and what is the science behind this soothing, natural and neurologically calming sound?
What is pink noise, and what is the science behind this soothing, natural and neurologically calming sound?
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From pink noise to brown, here’s what each sound frequency does—and how to use them for your wellbeing
Sound has long played a role in health rituals—from chanting and drumming to sound baths and binaural beats—but recent research has brought new focus to specific noise frequencies as tools for cognitive performance and sleep hygiene. Terms like white, brown and pink noise are increasingly featured in wellness apps, therapy protocols and clinical studies. Each involves a different distribution of acoustic energy across the frequency spectrum, producing distinct effects on the brain and nervous system. Knowing how they work can help you use sound more intentionally.
What is coloured noise?
Coloured noise refers to sound signals that contain a mix of frequencies, but with different levels of power distributed across the spectrum. White noise, for example, maintains equal intensity across all audible frequencies, while brown and pink noise emphasise the lower end. These variations change how the brain processes the sound. Higher-frequency-dominant noises like white can increase alertness by masking sudden changes in the environment, while low-frequency-heavy sounds like brown or pink may help down-regulate the nervous system. Choosing the right noise depends on what you’re trying to achieve—mental focus, emotional regulation or better sleep.
White noise: the broad-spectrum standard
Above White noise can help light sleepers stay asleep by masking background interruptions.
White noise distributes equal power across every frequency in the audible range—roughly 20 Hz to 20,000 Hz—resulting in a flat, uniform sound profile. This consistent intensity means it produces a high-pitched hiss, often compared to radio static, an air conditioner or a hairdryer. Its even coverage makes it particularly effective at masking unpredictable background sounds such as traffic, conversation or doors closing, which is why it's often used in sleep machines, hospital wards and open-plan offices.
While white noise can help light sleepers stay asleep by reducing sudden sound interruptions, its high-frequency content can feel harsh or fatiguing over time, especially for adults with sensitive hearing. Some users also report that it feels unnatural or overly clinical, which may limit its usefulness for extended listening.
Brown noise: low and grounding
Above Brown noise is often likened to the distant rumbling of thunder or heavy rainfall.
Brown noise—also called Brownian or red noise—intensifies the low end of the frequency spectrum by reducing power by 6 decibels per octave as the frequency increases. This means lower frequencies, especially those below 500 Hz, dominate the sound profile. Like white noise, brown noise spans the full audible range of 20 Hz to 20,000 Hz, but with a steep drop-off in intensity as it moves into higher pitches.
The result is a low, rumbling sound that lacks the sharpness of white noise. It’s often likened to distant thunder, heavy rainfall or the drone of a plane engine—sounds that many find physically soothing. On streaming platforms, users with ADHD have embraced brown noise for tasks that require sustained attention, describing it as less intrusive and more immersive than other noise profiles. While there’s limited clinical evidence so far, the anecdotal popularity has driven interest in further research on its impact on cognitive regulation and sensory processing.
Pink noise: the sleep-frequency favourite
Above Pink noise often comes up in sleep apps, resembling steady rainfall or the gentle rustle of leaves.
Pink noise reduces power by 3 decibels per octave as frequency increases, creating a more balanced distribution of energy across the spectrum compared to white noise. While it still spans the full range of human hearing (20 Hz to 20,000 Hz), the emphasis on lower frequencies gives it a softer, more natural sound profile. It often resembles steady rainfall, wind through trees or the gentle rustle of leaves—making it less abrasive and more sustainable for long-term listening.
Because pink noise contains less high-frequency content, it avoids the sharp hiss of white noise, which some listeners find fatiguing. This has made it a popular choice in sleep environments, particularly among people sensitive to sound. Several studies have explored its potential cognitive and physiological effects. Notably, a 2017 study published in Frontiers in Human Neuroscience found that older adults who were exposed to pink noise during deep sleep showed enhanced slow-wave activity (a marker of deep sleep) and improved memory recall the following day.
Not all noise is disruptive. When used with intention, coloured sound can offer clarity, calm or cognitive support. Understanding how white, brown, green and pink noise distribute their frequencies lets you tune your environment with more precision—one frequency band at a time.
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Chonx Tibajia is a senior editor at Tatler Asia’s T-Labs team, where she writes widely on lifestyle subjects including beauty, style, entertainment and travel. She has a long career in journalism, including roles as a columnist at The Philippine Star, and is the founder of the creative platform Pineappleversed. Beyond Tatler, her bylines appear in regional lifestyle and business publications, showcasing a broad portfolio that spans beauty trends, travel guides and culture pieces.
