Pink noise for baby sleep

What this sound is

In pink noise the power falls as the frequency rises, by about 3 decibels per octave. The result sounds balanced to a human ear, because our hearing is more sensitive to high frequencies and pink noise pulls exactly those back. Where white noise is hissy and bright, pink noise is fuller, lower and less piercing, close to steady rain, wind or distant surf. The name again comes from light: white light shifted toward red, the low-frequency end, looks pinkish. The pink noise in Agubu plays as a constant bed for as long as you need; the card in the app sums it up: softer than white, easier over long stretches.

Why it may help

The two explanations that apply to white noise apply here too: it resembles the continuous low rumble of the womb, and it masks sudden household sounds. Pink noise has one extra point in its favour: with fewer highs it is less irritating at the same perceived level, which suits long, quiet use. On the evidence, we know of no study that has looked at pink noise in babies specifically. When even the white noise evidence is weak and mixed, it would not be honest to claim more for pink. The plan is the same: try it for a few nights and read your own log.

Safe use

Because pink noise sounds gentle there is a temptation to turn it up; the volume rule does not change with the colour of the noise. Details are in the white noise guide.

• Keep the volume low: the level recommended for hospital nurseries is about 50 decibels. The practical test is simple: if you can talk in a normal voice in the room and still be heard easily, the level is fine; if the sound drowns you out, it is too loud.
• Do not put the phone or speaker in the cot or on its edge. Keep it at least one to two metres away, and avoid headphones, sound toys attached to the cot and any speaker close to the baby's ear.
• Use the timer. Fading the sound out 20 to 30 minutes after your baby has fallen asleep is usually enough. If you leave it on through the night, keep the level genuinely low.
• Turn it down once your baby has settled, and do not let a loud setting become the habit even briefly. Do not leave it running all day while your baby is awake, because it masks the speech they learn from.
• Soft does not mean close: the distance rule is the same as for white noise, at least one to two metres.

How to play it in Agubu

1. Open Agubu, go to the Sounds tab at the bottom and tap the Pink noise card under Noise. This sound is in the free tier; there is no account to create and nothing to download, it plays on your device offline.
2. Set the volume with your own ears first: if you can speak in a normal voice in the room and still be heard, it is low enough. Place the phone one to two metres from the cot.
3. Tap Timer and pick a duration. When it runs out the sound does not stop abruptly; it fades down slowly. Twenty to thirty minutes after your baby has fallen asleep is enough on most nights.
4. If you like, layer it in the Mixer: a light rain layer under pink noise adds a natural depth. The Mixer is a Premium feature and blends up to four sounds at separate levels. Sounds play without ads and the app needs no internet connection.

When to use it

• Through the night for a baby who wakes easily between sleep cycles, kept very low as a constant background.
• In the evening fussy hour when white noise seemed too harsh, as the softer alternative.
• When the sound has to be bearable for parents sharing the room; pink noise wears on adults less.