Waterfalls, White Noise, & Sweet Dreams: The Science of Sleep Sounds

It’s 3AM and you’ve just been jolted awake by the sirens of an ambulance driving past your window. Now you’re lying in bed listening to every little noise coming into your bedroom, and sleep is drifting out of reach. We’ve all been here at some point, but thankfully there’s a solution: Sleep sounds. 

Sleep sounds like the quiet murmurs of a distant waterfall or consistent frequency noises like white noise and pink noise are fantastic tools to help you fall asleep and stay asleep, ensuring you’re getting the high quality rest you need to feel your best. 

While conventional wisdom may once have emphasized the importance of sleeping in a silent environment, this isn’t an option for many. In our increasingly urbanized and noise-filled world, sleep sounds provide us with a way to control what sounds we hear in our nighttime environment, thereby increasing the quality of our rest. 

Different kinds of sleep sounds have different benefits, so you’ll have to experiment to find the ones that work best for you. Generally speaking, however, sleep sounds enhance our bedtime experience in two key ways. 

• Sleep sounds help us relax. Feeling comfortable and relaxed is a prerequisite for good sleep. Natural sleep sounds like rain falling or waves breaking make our brains feel safe, which allows us to relax and unwind. Artificial sleep sounds like white noise also help us relax by giving our brains a steady, soothing sound to focus on, in turn reducing brain stimulation and anxiety levels.
• Sleep sounds make it easier to stay asleep. Once they’ve helped you fall asleep, white noise and other sleep sounds help mask unexpected noises like car alarms or dogs barking that might otherwise have woken you up. Our brains perceive sudden, loud noises as threats and activate our “fight-or-flight” response which jolts us awake. Sleep sounds like running water and pink noise provide acoustic camouflage – drowning out those threatening noises with consistent, calming noise that lets us continue sleeping peacefully. 

There are many sleep sound options, but the best sleep sounds usually fall into one of two categories: Natural sleep sounds or artificial “color” noises like white noise. With a device like Restore 2 and Hatch Membership, you can access dozens of different sleep sounds – both natural and artificial – with the touch of a button. Let’s take a look at these two different kinds of sleep sounds and preview a few of our most popular sleep noises. 

White noise is one of the most famous and popular sleep sounds – and for good reason. Thanks to its exceptional acoustic camouflage capabilities and steady, soothing cadence, white noise has the power to lull us to sleep and keep us asleep all night long. 

What is White Noise? 

White noise is every frequency we can hear, played together at the same volume. The result is a “wall of sound” similar to the static of an empty radio channel or the noise a fan makes. It takes its name from white light, which is made up of every color of light we can see. 

White noise excels in masking disruptive outside noises that might wake you up. Instead of overpowering external noises it simply covers them up, melding them with its own frequencies. By incorporating other noises into its existing wall of sound, white noise effectively hides noises that might have woken us up. 

This acoustic camouflage is especially helpful for city dwellers: a survey of New Yorkers living in noisy environments found that using white noise for sleep “significantly improved” their rest quality by masking out unwanted sounds like sirens and door slams. 

White Noise and Its Variations

White noise isn’t the only “color” noise that can improve your sleep quality. Hatch's Restore 2 bedside sleep guide and sunrise alarm clock has three different colors of sound, all of which mask unwanted noises and promote relaxation. 

• White Noise: The classic original “color” sound – also known as a broadband sound –  white noise does it all. Sleeping with white noise can reduce stress and anxiety, help you fall asleep up to 40% faster, and stay sleeping all night long. Oh, and it’s the perfect sound to lull your newborn or toddler to sleep, because it mimics the sounds they heard in the womb. Want to hear more? Check out this sample of white noise.
• Pink Noise: Pink noise also plays every frequency we can hear simultaneously, but it increases the volume of low-end frequencies while reducing the volume of high-end ones. The result is a deeper sound, akin to the noise a waterfall makes, that’s perfect for drifting off to. Pink noise actually enhances deep sleep, which is a crucial part of the sleep cycle where the body rejuvenates itself. Interested? Here's a sample of pink noise.
• Brown Noise: Brown noise emphasizes low-end frequencies and lower high-end ones even more than pink noise. It plays a rich, low tone often equated to the sound of heavy surf breaking on the beach. If you’re looking for something without the characteristic “hiss” of white noise, look no further. And click here to hear a sample of brown noise.

If broadband sounds like white noise aren’t what you want to hear at bedtime, the natural world has a solution for you. Nature produces a myriad of soothing noises that help promote relaxation and offer acoustic camouflage capabilities. You’ve probably heard that it’s easier to fall asleep when you’re listening to rain fall, but the sound of waterfalls, breaking waves, thunderstorms, and even wind can have similar effects. 

Natural sleep sounds work by lowering our natural “fight-or-flight” response. Listening to continuous natural sounds lowers our nervous system’s sympathetic response, which controls that “fight-or-flight” feeling. At the same time, these natural sounds are boosting our nervous system’s parasympathetic response. Our parasympathetic response dictates how relaxed we feel and how we act in “normal” situations (ones that don’t require a “fight-or-flight” response). Parasympathetic responses are sometimes called our “rest-and-digest” response, which is exactly what you’re looking for at bedtime. 

There are lots of different natural sleep noises to choose from, so finding the one that works best for you might require a bit of experimentation. Interestingly, we seem to respond more positively to natural noises we’re already familiar with, so if you grew up near the beach listening to the waves every night, the sound of breaking surf might be what you’re looking for. 

We recommend trying different natural sleep noises until you find one that clicks. With a Hatch Membership and Restore 2, you’ll have dozens of natural sounds to choose from, carefully curated from around the world to provide you with high-quality sleep. Doze off to breakers hitting the beaches of California, waterfalls in Iceland, or the nocturnal sounds of a lush forest. 

Whichever sleep sound you choose, the sounds on Restore 2 make it easy to set up, play, and experiment with sleep noises. To get the most out of your chosen sleep sound, we recommend that you keep it playing all night. Using a video or audio file may work, but you run the risk of encountering disruptive ads or waking up to external noises if the sleep sound restarts or shuts off. 

With Restore 2, you can easily change the volume without turning on a screen, and set your sleep sound to play continuously for as long as you need. And a Hatch Membership provides you with top-quality sleep sounds which you can preview and add to your bedtime routine with the click of a button. 

See why Hatch customers love Restore 2, and learn more about how this bedside sleep guide and sunrise alarm clock can turn bedtime into a delight for you and your entire family.