If you've ever slept in a city apartment, near a highway, or next to a partner who snores, you already know the problem: your brain won't stop listening. Every car horn, door slam, and sudden creak pulls your nervous system out of sleep, sometimes fully, sometimes just enough to wreck the quality of whatever rest you're getting. The usual advice for this is simple: use white noise to mask the disruptions. But what most people miss is that masking noise is only half the equation. The other half is getting your brain deep enough into sleep that those disruptions stop mattering at all.
That's where binaural beats come in. And the idea behind layering the two is to get something neither does on its own.
Does white noise help you sleep?
White noise can help with sleep in noisy environments, though the data on white noise in general is mixed. White noise works mainly as a shield: it raises the baseline sound level in the room so sudden spikes, such as a dog barking or a door slamming, stand out less. Masking does not, on its own, make sleep deeper.
The research on white noise is mixed. A 2021 systematic review in Sleep Medicine Reviews (Riedy and colleagues, University of Pennsylvania) covered 38 studies of continuous noise and rated the quality of evidence that it improves sleep as very low, with some studies finding a benefit and others finding disruption. Where white noise has the best case is in noisy environments, where there are real disturbances to cover.
Pink noise, a variant with more bass and less treble, is often suggested as an alternative. A 2022 systematic review in the Journal of Clinical Sleep Medicine (Capezuti and colleagues) found that 9 of 11 pink noise studies reported improved sleep outcomes, compared with 6 of 18 white noise studies, though the quality of the studies was uneven. Many people also find pink noise more natural-sounding than pure white noise (think rainfall or ocean waves instead of TV static) and less tiring to listen to over long periods.
But here's the critical point: white noise and pink noise work primarily as shields. They raise the baseline ambient sound level in your room so that sudden spikes (a dog barking, a truck braking, your neighbor's 1 AM door slam) don't punch through the silence and trigger your brain's threat-detection system. That's the concept of auditory masking, and it is the most plausible reason noise helps in loud settings.
The science of auditory masking
A 2021 study published in Sleep Medicine by researchers at Weill Cornell Medical College (Ebben, Yan and Krieger) tested a white noise machine with 10 adults who lived in high-noise environments in New York City and had trouble sleeping. During the week with white noise, participants spent less time awake after falling asleep (measured by actigraphy) and reported falling asleep faster. It is a small study, but it fits the masking idea: when there's already a consistent layer of broadband sound in the room, a sudden noise needs to be proportionally louder to register as a disturbance.
A 2025 systematic review by Mayo Clinic researchers (Khandelwal and colleagues, Sleep Medicine: X) screened 1,920 records and found seven randomized trials, covering 496 hospitalized adults, that tested sound machines. The authors concluded that white noise and similar masking sounds seem to improve sleep efficiency in hospital patients (one of the noisiest environments a person can try to sleep in), while noting that the trials were few and too different from each other to pool. In one coronary care unit study (Farokhnezhad Afshar and colleagues, Journal of Caring Sciences, 2016), patients without white noise saw their average sleep fall from about 7 hours to under 5 after three nights in the unit, while patients given white noise held steady.
The principle behind all of this is simple. Your brain doesn't fully shut off its auditory processing during sleep - it can't, because hearing evolved as a survival mechanism. Sounds are constantly being evaluated at a subconscious level, and anything that deviates sharply from the baseline ambient noise triggers an arousal response. White noise makes the baseline consistent. No sharp contrasts means fewer arousals.
The problem white noise doesn't solve
Here's what most articles about white noise leave out: masking noise doesn't make your sleep deeper. It just removes some of the things that make it shallower. There's a meaningful difference.
White noise can prevent you from being pulled out of sleep by external sounds, but it doesn't actively push your brain into the deeper stages of sleep - the slow-wave delta sleep where your body does its heaviest repair work, consolidates memories, clears metabolic waste from the brain, and resets your immune system. If you're someone who lies awake with a racing mind, or who falls asleep but never feels truly rested in the morning, masking noise alone isn't going to solve the underlying problem. Your brain is staying in lighter sleep stages, cycling through N1 and N2 without spending enough time in N3 deep sleep.
This is where the research on binaural beats becomes relevant - and where the idea of combining the two approaches comes from.
How binaural beats may push sleep deeper
We covered the science of binaural beats in detail in our previous post on binaural beats and sleep, but here's the essential framework: when your ears receive two slightly different frequencies - one in each ear - your brainstem perceives a third tone at the difference between them, and, in theory, your neural oscillations begin to synchronize toward that frequency. This proposed effect is called brainwave entrainment, and the evidence for it is mixed.
For sleep specifically, the frequencies that matter are delta (1 to 4 Hz) and theta (4 to 8 Hz). Delta waves are the signature brainwave pattern of deep slow-wave sleep. Theta waves characterize the transition zone between wakefulness and sleep - that drowsy, pre-sleep state where your thoughts start to dissolve. The idea behind presenting binaural beats in these frequency ranges is to give your brain a target to synchronize toward, rather than just hoping it gets there on its own. If you want the full breakdown of which Hz value works best inside the delta band, our piece on the best binaural beat frequency for deep sleep walks through the research.
A 2024 University of Tsukuba study published in Scientific Reports (Fan, Zhu and colleagues) tested this with 12 healthy adults during 90-minute afternoon naps and found that binaural beats at 0.25 Hz shortened the time it took to reach both N2 and N3 sleep compared with no sound. The same study did not find measurable entrainment of brain activity at the beat frequency, so the mechanism is still unclear, and a nap study in 12 people is an early result, not proof for overnight sleep.
In other words: white noise is there to keep disruptions from pulling you out. Binaural beats are meant to help you in. This combination is core to comprehensive methods for falling asleep faster.
Can you use white noise and binaural beats together?
White noise and binaural beats can be used together, and they do different jobs. The white noise layer handles the environment by masking sudden sounds, while low-frequency binaural beats are meant to encourage the brain toward slower delta activity. Keep the binaural beats quieter than the masking layer, and use headphones so each ear gets its own tone.
Think of it as a defensive layer and an offensive layer working in concert.
The white noise layer handles your environment. It creates a consistent acoustic floor that raises the threshold for auditory arousals. Sudden noises - traffic, HVAC cycles, roommates, wind - get absorbed into the broadband sound rather than spiking above the silence. Your brain's threat-detection system stays quiet because there are no sharp contrasts to evaluate.
The binaural beats layer handles your brain. While the white noise keeps external disruptions from fragmenting your sleep, the low-frequency beats are meant to encourage your brainwaves toward delta frequencies, which in theory would deepen your sleep and make it more resilient. When you're in deep N3 slow-wave sleep, your arousal threshold is already significantly higher than in lighter stages. You're naturally harder to wake. The masking noise has to do less work because your brain is in a state that inherently filters out more.
This is the key insight: the deeper you sleep, the less noise matters. Deep slow-wave sleep has the highest arousal threshold of any sleep stage. A sound that would easily wake you during N1 or N2 light sleep might not even register during N3. So if binaural beats do help you reach deep sleep, they would also make the white noise's job easier, because your brain would be in a state where external sounds have less power to disturb you.
Why the mix matters more than most apps realize
Most sleep apps treat white noise and binaural beats as separate features. Pick one or the other. Maybe they let you play rain sounds. Maybe they have a "binaural" category somewhere. But they almost never integrate the two in a way that respects the underlying neuroscience.
The problem with pure binaural beats in isolation is practical: they need to be audible to work, but they're tonal and repetitive, which some people find difficult to fall asleep to. And binaural beats are unlikely to do much if they are buried under heavy ambient sounds that mask the beat itself, since both tones have to be clearly audible, one in each ear, for the brain to register the difference.
The solution is careful layering with independent volume control. You want the white noise or nature sounds at a level that masks your environment, and the binaural beats at a softer level underneath - present enough for your brainstem to pick up the frequency differential, but not so loud they become distracting. This is a balance that a single volume slider can't achieve. You need control over each layer independently.
How IOn Sleep handles this
IOn Sleep was built with exactly this layering approach in mind. The app lets you mix up to three independent sound layers - each with its own volume control. You can set a white noise or rain layer at whatever level masks your environment, then add a delta or theta binaural beat layer underneath at a softer volume, and optionally add a third ambient texture (a low rumble, a distant storm, a river) to round out the soundscape.
For people who want the two-layer approach without manual mixing, IOn Flow automates the binaural layer. It starts in the alpha range for wind-down, moves through theta, settles into delta for the main stretch of the night, and returns toward alpha before your wake time, all while you can layer environmental sounds on top at your preferred volume. Sequenced programs like this are something researchers are still testing: a 2023 study protocol in Frontiers in Neurology (Gantt) sets out a trial of sequenced theta and delta beats, on the reasoning that a single fixed frequency may not carry a listener through the phases of sleep. A protocol is a plan for a study, not a result.
And because IOn Sleep plays everything offline and needs no account, you can leave your phone in airplane mode all night. Your phone becomes a sound engine, which is what it should be at 2 AM.
How do you layer white noise and binaural beats?
To layer white noise and binaural beats, set the masking sound just loud enough that individual noises from your environment stop standing out. Add binaural beats underneath at a lower volume, starting with theta (4 to 8 Hz) and switching to delta (1 to 4 Hz). Use headphones or earbuds, and consider a sleep timer.
If you want to try the two-layer approach, here's a sensible way to set it up:
Choose your masking layer. White noise works, but pink noise has its own research behind it, and nature sounds (rain, ocean, fan) tend to be more comfortable for long-duration listening. Set the volume just high enough that you can't clearly distinguish individual sounds from your environment. That's your masking threshold. For most adults it lands somewhere between 50 and 70 decibels at the pillow, and our guide to how loud white noise should be for sleep explains how to check.
Add binaural beats underneath. Start with theta (4–8 Hz) for the first 15–20 minutes as you wind down, then switch to delta (1–4 Hz) for the rest of the night. Or use a dynamic program like IOn Flow that handles the transition automatically. Keep the volume lower than your masking layer - the beats should be audible but not dominant.
Use headphones or earbuds. Binaural beats require separate frequencies in each ear. Speaker playback won't deliver a separate tone to each ear. Comfortable sleep earbuds or a headband speaker are worth the investment if you're serious about this approach.
Consider a timer. Continuous sound all night isn't necessary for everyone. If your main problem is falling asleep, the first 30 to 60 minutes are when masking matters most, and a timer also limits how many hours of sound your ears get. If noise tends to wake you later in the night, all-night playback may suit you better. IOn Sleep's sleep timer lets you fade everything out gradually so the silence doesn't jolt you awake.
The bottom line
White noise can mask the disruptions that fragment your sleep. The evidence for that is strongest in noisy environments and thinner elsewhere. But masking is defense. It keeps bad things from happening. It doesn't actively make good things happen.
Binaural beats in the delta and theta range are the proposed offensive counterpart: early studies suggest they may help the brain settle into deeper sleep stages, where external sounds have less power to disturb you. Layering the two is a reasonable thing to try. One layer shields you from your environment while the other may nudge your brain toward deep, restorative sleep.
No study has yet tested this exact combination head to head, so treat it as an experiment worth running on yourself. It's the approach IOn Sleep was designed to make easy.
This post is part of our sleep guides.