White
0 dB / octave
Equal energy at every frequency. Because we hear in octaves, it sounds bright and hissy — the classic "TV static".
Shepard tone.
A sound that keeps rising and never gets higher. Listen to the endless glide and the endless scale, then an ordinary scale for comparison, and see the trick behind it.
Now playing
Deep sleep
Listen to it rise for ever
Tap an example to play it, and again to pause. Give the rising tone a minute: it never arrives anywhere. The live picture shows its tones sliding under a curve that stays put.
How the Shepard tone works
A Shepard tone is not one pitch but several, an octave apart: 55, 110, 220, 440 Hz and so on, all sounding together. A fixed curve sets how loud each one is: the middle ones loud, the lowest and highest so quiet you cannot hear them. As every component rises, the top one fades into silence while a new one fades in at the bottom.
Your ear follows each step up but never notices the hand-over, so the tone seems to climb without end. Roger Shepard made the stepping version in 1964; Jean-Claude Risset made the smooth, endless glide a few years later. Film composers use it for tension that never resolves, and the endless staircase in Super Mario 64 plays it.
Good to know
- After 12 steps of the Shepard scale every frequency is back where it began: step 13 is exactly the same sound as step 1.
- It works because the ear judges each move from the step just before, and each step really does go up. What stays ambiguous is which octave the tone belongs to.
- Christopher Nolan built the score of Dunkirk (2017) around a Shepard tone, so the tension keeps rising to the end.
- Its visual twin is the Penrose staircase, the endless stairs M. C. Escher drew in Ascending and Descending.
| What plays | What you hear | |
|---|---|---|
| Endless rising tone | Tones an octave apart glide up together; the top one fades out as a new one fades in at the bottom | A climb that never ends |
| Shepard scale | The same in semitone steps: after 12 steps every tone is exactly where it started | A scale that keeps going up |
| Ordinary scale | One tone with its harmonics, C4 up to C5, then back | A rise, then an obvious drop |
| Faster rise | An octave every 3 seconds instead of every 10 | Rising tension, as in film scores |
What is a Shepard tone?
An auditory illusion: a sound made of tones an octave apart that seems to rise or fall for ever, because the top tones fade out as new ones fade in at the bottom.
Who invented the Shepard tone?
The cognitive scientist Roger Shepard, in 1964. The composer and physicist Jean-Claude Risset later made the continuous gliding version.
Why does it feel tense?
Every moment sounds like a rise towards something, and nothing ever arrives. Film and game music use it for exactly that feeling.
Mixes
Pick what you need. One tap to start, change anything and save it as your own.
Focus timer
Work in waves.
The Pomodoro rhythm: focus with calm sound in your ears, then take a real break. A soft bell marks every change, so you never watch the clock. Every fourth break is a long one.
Every fourth break is twice as long.
25:00Focus · 1 of 4
Sound while you work
Breathe
Slow your breathing down.
Follow the circle and the sound: it rises as you breathe in and falls as you breathe out. Choose a rhythm, or set your own, and pick what plays underneath.
Ready
Sound while you breathe
Noise generator
Any color of noise, from deep brown to bright violet — and everything in between.
Brown noise
Spectrum · 20 Hz – 20 kHz
Sound science
The colors of noise
Same randomness, different tilt. Each color shifts energy between low and high pitches — here is what that sounds like.
Pink
−3 dB / octave
Equal energy in every octave, so it sounds even to the ear. Steady rain, rustling leaves. A favorite for focus.
Brown
−6 dB / octave
Deep and warm, like a distant waterfall or a plane cabin. Masks voices and traffic without any hiss.
Grey
Equal-loudness curve
Shaped around how our hearing works, so every pitch seems equally loud. Balanced and soft.
Blue
+3 dB / octave
The mirror of pink: more treble than bass. Airy, crisp, like a light spray.
Violet
+6 dB / octave
Mostly treble, like hissing water. Sometimes used to mask high-pitched ringing.
Calm
Gentle tones to settle into: singing bowls, a slow warm drone, wind chimes tuned so every note fits.
Frequencies
Famous tones on pages of their own: hear them side by side, with honest facts.
Sound phenomena
How sound bends, shifts, rings and fools the ear, and why space is silent: hear it for yourself.
Nature
Rooms & travel
Animals & countryside
A purring cat, whales and dolphins, a nightingale in the dark, cowbells on a summer pasture. Wonderful in stereo.
For babies
Womb sounds are what a baby heard for nine months: a deep rush of blood flow, and the heartbeat.
Hearing and speaker tests
Check your ears, headphones and speakers, each test on a page of its own with a live picture.
Ear Age · 60 seconds
Test your ears.
Our ears lose the highest pitches first, and it starts early. Find the highest tone you can still hear and see the typical age for it.
- Headphones on, quiet room
- Set a comfortable volume on the 1 kHz tone
- Don't turn it up when a tone disappears — that's the point
Step 1 · Volume
Play the reference tone and set your volume so it's clear but comfortable. Leave it there.
Step 2 · Listen
8,000Hz
Your result
8k12k16k20k
A rough guide, not a diagnosis. Your phone, headphones and even this browser can cut the highest tones. Worried about your hearing? See an audiologist.
More ear tests
Check your headphones, find the deepest bass your setup can play, or play any pitch you like.
Headphones check
Left & right
Each ear should get its own side. It matters for 8D, binaural beats and every stereo sound here.
Headphones on, then tap a side.
Bass test
How low can you go?
Deep tones from 200 Hz down to 20 Hz, the bottom of human hearing. Mostly it tests your speakers or headphones.
200Hz
Your setup plays down to
Tone generator
Any pitch, 20 Hz – 20 kHz
Hz
Start quiet: high tones and square waves get tiring fast.
Take it to bed
An app without the app store.
Add Ears & Waves to your home screen and it opens like any app — full screen, with its own icon. Everything it needs is saved on your device, so it keeps playing on a plane, in a tent or with Wi-Fi off.
Preparing offline mode…
- Works offlineNo streaming. Sound is computed on your device, forever.
- Screen offKeeps playing with the phone locked. The timer fades it out gently.
- PrivateNo account, no ads, no cookies. Your mixes stay on your device.
