Sound Machines

When it comes to helping your baby settle and stay asleep, there are plenty of tools and tips out there, but one of the most commonly recommended is a sound machine. If you’ve ever wondered “Should I be using one?” or “Is this just another baby product I don’t need?”, you’re not alone. Let’s discuss it.

What is a sound machine?

A sound machine plays continuous background noise, which can help block out external sounds. There are different types of noise, but here are the most common ones:

• White noise (static-like, even sound)

• Pink noise (gentler, lower-pitched)

• Brown noise (deepest tone)

  
  

What about other sounds, like lullabies, heartbeat, or nature sounds?

Many sound machines offer options like lullabies, heartbeat rhythms, or nature sounds, such as ocean waves, rainforest sounds, and rain. I don’t recommend using these for sleep.

Why? These sounds change in pitch, frequency, or rhythm. While they may be soothing during the wind-down routine, once your baby is asleep and enters a lighter phase of sleep, any subtle change in sound can actually cause them to wake. Their brain notices the shift, even if it’s gentle, and this can disrupt their sleep.

How does a sound machine block external sounds?

A consistent background sound helps "drown out" other noises in the environment. Think of it like audio camouflage.

Here’s how it works:

When your baby is sleeping in a quiet room, any sudden sound, like a creaky floorboard, loud voice, or a dog barking, can feel jarring and wake them up. But when you have a sound machine playing, that sudden sound doesn’t seem as loud in comparison because the background noise masks the change.

It’s not that the sound disappears completely, it’s that the machine makes it less noticeable by reducing the contrast between silence and the new sound. This helps prevent those unexpected noises from startling your baby awake during lighter sleep phases.

All the reasons you should use one:

✅ Blocks out household noise: Coughing, creaky floorboards, barking dogs, siblings playing, etc.

✅ Helps with early rising: In the early hours of the morning, typically around 4–5am when we’re in our lightest phase of sleep, melatonin levels drop, sleep pressure is low, and we’re more prone to waking from even the slightest sounds. This is when external noises like birds chirping, cars driving by, a neighbour leaving for work, or even the garbage truck can easily wake your baby.

✅ Signals it's sleep time: Over time, your baby will learn that when the sound machine is on, it’s time for sleep. It becomes a powerful cue in your sleep routine.

✅ Mimics the womb: Babies are used to noise. The womb is surprisingly loud, filled with the constant whoosh of blood flow, heartbeat, and digestion. After birth, the sudden quiet can feel unsettling. Sound machines recreate that comforting, familiar environment. Combine it with a pitch-black room, and you’ve just recreated the calming ambience of the womb. For more ways on creating a sleep environemnt to encourage better sleep, read this blog.

✅ Can help calm an unsettled baby: I often recommend turning the volume up slightly when your baby is unsettled, then lowering it once they’ve calmed down or fallen asleep.

Is it safe?

Yes, as long as it’s set to a safe volume. This is usually between 60-70 decibels (about the level of a running shower) and placed 1–2 metres away from them.

If you’re unsure, many smartphones have free decibel reader apps you can download. For the most accurate reading, place your phone in the cot or where your baby sleeps, not next to the machine. Measuring it too close to the source can give you a misleading result.

Common safety and development concerns:

These are questions I get asked a lot, and it’s completely valid. As parents, it’s natural to worry about anything that might affect your baby’s safety and development. Here are some common concerns:

Hearing loss: Rest assured, when used correctly, a sound machine is not harmful to your baby’s hearing. The risk of hearing damage comes from volume and proximity. Just like with any sound source, if the sound is too loud or placed too close to your baby for long periods, it can pose a risk.

Auditory processing: There’s currently no evidence that a sound machine interferes with a baby’s ability to develop speech or process sounds, especially when used only for naps and night sleep. During wake times, your baby is still hearing your voice, environmental sounds, and plenty of rich language exposure, which is what truly supports auditory development.

Overstimulating: White, pink or brown noise is a non-stimulating, steady sound, unlike lullabies or nature sounds that vary. It doesn’t grab your baby’s attention, it soothes and settles them.

Impact brain development or sensory processing: Some parents worry that using a sound machine might dull a baby’s sensory awareness or limit brain stimulation. In reality, a sound machine is only used during sleep times, when the brain isn’t actively engaging with the environment anyway.

Your baby still receives plenty of auditory and sensory input during the day, which is when brain development and sensory learning are most active. There’s no research to suggest that a sound machine used at safe levels during sleep negatively impacts cognitive or sensory development.

Affects REM or deep sleep quality: No, if anything, a sound machine can actually enhance sleep quality. By helping babies stay asleep through external disturbances, they’re more likely to cycle through full, uninterrupted stages of sleep, including REM (which is essential for brain development).

Overheat or pose a fire risk: As with any electronic device, it's important to follow basic safety:

• Use a machine that meets safety standards.

• Keep it well ventilated and out of the cot.

• Place it on a stable surface, away from bedding or soft materials that could cover it.

  
  

Bluetooth or Wi-Fi: If your sound machine has smart features (like app control or Wi-Fi), you might be concerned about EMF (electromagnetic field) exposure. While current evidence shows no proven harm from low-level EMF exposure, you can always choose a basic, non-Wi-Fi model if you’d prefer to minimise any wireless emissions in your baby’s sleep space.

How long should it play for?

Your sound machine should run for the entire duration of your baby’s nap or overnight sleep.

Avoid machines with automatic shut-off timers. You want the sound to stay consistent throughout the whole sleep. If it stops, it can cause your baby to wake fully.

Where should it be placed?

Place the sound machine between your baby’s cot and the main source of noise, like a door, hallway, or window. This placement helps block out external sounds more effectively.

If you have twins or room-sharing siblings, position it between their cots to help mask each other’s noises.

Will your baby become dependent on the sound machine?

This is one of the most frequently asked questions. The truth is: Yes, your baby may come to associate a sound machine with sleep, and that’s actually the whole idea. It’s no different from other positive sleep associations like a dark room or a bedtime routine.

Will it prevent your baby from learning to sleep in silence and rely on the sound machine?

You want your baby to be flexible and able to sleep anywhere, anytime. But here’s the truth:

Yes, babies can learn to sleep in different environments, but that doesn’t mean every environment is ideal for deep, restorative sleep. Trying to get your baby to “tough it out” in loud or unpredictable settings often means they end up getting fragmented, lighter sleep. Their brain never fully switches off, and they spend more time in lighter sleep stages, making them more prone to wake-ups, overstimulation, and overtiredness.

Let’s flip the perspective, would you rather your baby “get used to” sleeping in a noisy environment, or consistently get better quality sleep in a quiet, controlled space that supports their development?

Research shows that frequent disruptions to sleep, like loud noises or environemnts, can affect mood regulation, and overall sleep quality.

When to wean a sound machine?

There’s no specific age at which you “must stop” using one. Many toddlers (and even adults) benefit from it. If you do want to phase it out, it can be done gradually, just like any other sleep association. All you have to do is gradually decrease the volume each night.

Here's a fun fact:

Did you know, studies show that over 80% of babies fall asleep faster and stay asleep longer when white noise is used? It helps reduce the time it takes for them to settle and increases the length and quality of their sleep.

Will it fix your little one's sleep?

Sound machines aren’t a magic fix, but they are a gentle, effective tool to support better sleep. They create consistency, mask disruptions, and help babies feel secure.

Better sleep isn’t just about one thing. Think of it like layers working together. A sound machine is just one piece of the puzzle, alongside a pitch-black room, comfortable room temperature, appropriate wake windows, and your little one learning how to fall asleep without assistance, plus other factors. When these elements come together, that’s when sleep really starts to improve.

Struggling with sleep?

If your baby or toddler is struggling with naps, nights, early wakes, or if they wake at the tiniest sound, it might be worth introducing a sound machine.

If you're wanting more sleep tools and guidance? My downloadable sleep guide can help you. It's the perfect how-to guide for better sleep.

If you feel you might need more personalised support, I offer phone consults, and one-on-one support through plans. These services allow us to work closely together and address your specific needs.

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I'm the founder of Babee Dreams, a certified sleep consultant, and a mum of three. Everything I share is from evidence-based research, professional training through The Sleep Consulting Academy, real-life success stories from families I've worked with, and the instincts that come from being a mum.

Disclaimer: This blog is for informational purposes only and is not a substitute for professional medical advice. Always consult your healthcare provider for personalised guidance regarding your baby's health and well-being. Babee Dreams does not give medical advice.