White
0 dB / octave
Equal energy at every frequency. Because we hear in octaves, it sounds bright and hissy — the classic "TV static".
Harmonics and overtones.
Every note you play is a stack of tones: the note itself and its harmonics, two, three, four times its frequency. Hear them one by one, see which notes they are, and build a sound from them.
Now playing
Deep sleep
Listen to the harmonics
Tap an example to play it, and again to pause. The single harmonics play the fundamental first, then the harmonic, then both together. The picture shows each harmonic and its note.
What harmonics are
A string or a column of air vibrates as a whole, but also in halves, thirds, quarters and so on, all at once. Each part vibrates faster: twice the frequency, three times, four times. These are the harmonics, and together they make the harmonic series. On A2 at 110 Hz they are 220, 330, 440, 550 Hz and up.
In music they are intervals: the 2nd harmonic is an octave above the note, the 3rd an octave and a fifth, the 4th two octaves, the 5th two octaves and a major third, and the 4th, 5th and 6th together make a major chord. How strong each harmonic is gives an instrument its colour, its timbre: a flute has few, a violin or a trumpet many.
Good to know
- Harmonics are not quite the piano’s notes: the 5th is 14 cents below its major third and the 7th 31 cents below its minor seventh. Barbershop singers and brass players often bend towards the natural ones.
- A bugle has no valves: every bugle call is played on the harmonics of one tube, from the 2nd to about the 6th.
- Overtone singers, for example in Tuvan throat singing, shape their mouth so one harmonic of their voice rings out as a whistling melody above the drone.
- Bells sound bell-like because their partials are not harmonics: they are not whole multiples of one frequency.
| Harmonic | On A2 (110 Hz) | Above the note |
|---|---|---|
| 1 (the fundamental) | 110 Hz, A2 | The note itself |
| 2 | 220 Hz, A3 | An octave |
| 3 | 330 Hz, E4 | An octave and a fifth |
| 4 | 440 Hz, A4 | Two octaves |
| 5 | 550 Hz, C♯5 | Two octaves and a major third (14 cents flat) |
| 6 | 660 Hz, E5 | Two octaves and a fifth |
| 7 | 770 Hz, G5 | A minor seventh, 31 cents flat |
| 8 | 880 Hz, A5 | Three octaves |
What is the difference between harmonics and overtones?
They are counted differently. The 1st harmonic is the fundamental itself, so the 2nd harmonic is the 1st overtone, the 3rd harmonic the 2nd overtone, and so on. Overtone is also used for partials that are not exact multiples.
What is the 2nd harmonic?
Twice the fundamental frequency, an octave above it: on A2 at 110 Hz, it is A3 at 220 Hz.
Why do instruments sound different on the same note?
They share the fundamental but not the balance of harmonics. Which harmonics are strong, and how they change as the note starts and fades, is what we hear as timbre.
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.
