Loud sound and your hearing

People who work with sound depend on their hearing, and hearing does not recover from certain kinds of damage. The basics are simple and worth knowing.

What loud sound does

Hair cells in the inner ear convert vibration into nerve signals. They can be overloaded and, if the loud sound is strong enough or lasts long enough, destroyed. They do not grow back.

• Temporary threshold shift (TTS). After a loud event, hearing is dulled for hours or days, and often with a ringing sound. A sign that the ears have been stressed.
• Permanent threshold shift. After repeated exposure, some of the loss no longer recovers.
• Tinnitus, a persistent ringing, is often a sign of damage and can become permanent.

Early noise damage usually appears around 3 to 6 kHz, where the ear is most sensitive and the ear canal resonates, and is often not noticed until it has spread to the speech range.

Level and time

The risk increases with both level and duration. Common criteria describe how long a level can be tolerated per day:

With a 3 dB exchange rate, every 3 dB increase halves the allowed time: 88 dB for 4 hours, 91 dB for 2 hours, 100 dB for about 15 minutes. The noise exposure tool calculates the dose.

These are limits for workplaces, not guarantees of safety. Rules differ between countries, and peak levels (for example impulses of 135 to 140 dB(C)) are covered separately.

Loud music

A rock concert at 100 to 110 dB(A) uses up the daily dose within minutes. Headphones can reach similar levels. Reading the level in dB(A) understates the load of bass-heavy music, see Weighting filters.

Protecting your hearing

1. Reduce the level or the time. Distance can help: outdoors or close to a single loudspeaker, each doubling of distance takes up to 6 dB off, see How sound falls with distance. That figure assumes a point source in a free field. In a club or hall, a line-array system and the reverberant sound mean the level can drop much less, so moving back alone does not tell you your dose; check with a meter or wear protection.
2. Take breaks in quiet. Hearing recovers when it is given time.
3. Use ear protection at loud events. Musician's earplugs reduce the level by roughly 15 to 25 dB with a fairly even frequency response, so that sound remains natural.
4. Monitor at moderate levels, and use a calibrated meter when mixing for long sessions.
5. Check your hearing regularly, particularly if you work in noise.

Safe sound generators

The signal generators on this website start at a low level and are capped for this reason. Pure tones and noise at high level can damage hearing and loudspeakers quickly.

Draft: written by an AI assistant, awaiting technical review. This is general information, not medical advice.