How to use it
Put on headphones, turn your device volume down and press Play. The first sound of every source starts in “Normal hearing”, so first raise the volume to a comfortable level. About a second later “Simulated loss” (key B) unlocks: the same sound is then filtered the way the chosen hearing profile would let it through. Switch back and forth while it plays.
Pick another profile, or drag the points of the audiogram to draw your own, separately for each ear.
Controls
- Play / Stop: starts and stops the sound. Esc stops everything, including the microphone.
- Normal hearing / Simulated loss: keys A and B. Space switches too when the focus is on the switch, the chart or the page background; on any other button it presses that button.
- Volume: the page’s own output level, with a fixed ceiling.
- Sound source: demo sounds, your own file (decoded in the browser, never uploaded, played in a loop) or the microphone, which starts only after you confirm that you wear headphones: loudspeakers would feed the sound back into the microphone and howl.
- Audiogram: drag a point up or down, or focus the chart and use the arrow keys: left and right choose a frequency, up and down change it by 5 dB. “Edit” selects the ear; the copy buttons make both ears equal.
- Use my result from the Hearing Test: loads the latest run saved in this browser by our Hearing Test. Those values are uncalibrated and approximate.
How it works
An audiogram shows, for each pitch from low (left) to high (right), how much louder than the average threshold of healthy young ears a tone must be before a person can just hear it. That number is the hearing level in decibels (dB HL). Larger values are drawn lower and mean more loss. By convention the right ear is a red circle and the left ear a blue cross.
The simulator turns each ear’s audiogram into a filter. At every frequency the sound is turned down by the hearing level at that frequency, with straight lines between the seven points on a logarithmic frequency axis:
Below 125 Hz and above 8 kHz the nearest value is used, and values better than 0 dB are not boosted. Each ear has its own linear-phase filter with a few thousand coefficients, which delays all frequencies equally by roughly 45 ms. The Normal position passes through the same delay, so switching is seamless.
Why does a high-frequency loss sound muffled rather than quiet? Vowels are strong and carry most of their energy below about 1 kHz, so a voice still seems loud enough. Consonants such as s, f, th and sh are much weaker hisses with most of their energy above 2 kHz, and they are what separates “sun” from “fun”. When they fall below the threshold, people say: “I can hear, but I cannot understand.”
What this simulation does not reproduce. It only turns sound down. Most permanent hearing loss is sensorineural: the inner ear or the hearing nerve is damaged. Such a loss usually also brings reduced frequency selectivity (neighbouring pitches blur into each other, so speech is much harder to follow in background noise), loudness recruitment (quiet sounds are inaudible, yet loud sounds are about as loud as for anyone else) and often tinnitus. That is why turning up the volume does not fully fix it, and why real life with such a loss is harder than this demo.
Things to try
- Play the speech-like sounds with “Age-related, about 70 years”: the vowels stay, the s and f hisses almost vanish.
- Play the bird song with the same profile, then with “Low-frequency loss”. Only one of them takes the birds away.
- Compare the 4 kHz notch with the steep high-frequency loss on the melody: the notch dulls one band, the steep loss removes almost everything above it.
- Choose the one-sided loss and listen to stereo music: one ear falls almost silent, and the sense of direction goes with it.
- If you have taken the Hearing Test, load your result and let a family member listen to a favourite song through it.
Frequently asked questions
Is this what hearing loss really sounds like?
Only roughly. The page reproduces which pitches become too quiet to hear. It does not reproduce the loss of clarity, the trouble in noise, recruitment or tinnitus that usually come with a real loss.
Can this page tell me whether I have a hearing loss?
No. It is a demonstration, not a test, a diagnosis or a prediction of anyone’s hearing. If you are worried, see a doctor or an audiologist. Hearing that drops suddenly, within hours or a few days, needs a doctor urgently, on the same day: treatment works best when it starts early.
Why can a hearing aid not simply fix it?
Amplification brings sounds back above the threshold, but a damaged inner ear also analyses sound less precisely, and loud sounds soon become uncomfortable. Hearing aids therefore amplify quiet sounds more than loud ones. They help a great deal, but they do not restore normal hearing.
Where do the profiles come from?
They are textbook shapes, not anyone’s measurement. The age profiles are rounded, illustrative values close to published typical values for men with no other ear disease. Women of the same age usually have less loss at high frequencies, and individuals differ widely.