128 Hz tone
A tuning-fork favourite.
Volume first. Turn your device volume down before pressing play, then raise it slowly. Tones start quiet on purpose. Keep headphones off your ears until you know how loud it is.
Hz
Logarithmic slider, 1 Hz to 22 kHz. Space bar starts and stops.Waveform
0 dBFS is the loudest your device can play; every 20 dB lower is a tenth of the amplitude.
What 128 Hz is used for
Clinicians use 128 Hz tuning forks for vibration-sense checks. As a tone it is a comfortable low reference that nearly any speaker can play.
| Period | 7.813 ms |
|---|---|
| Wavelength in air (20 °C) | 2.68 m |
| One octave down / up | 64 Hz / 256 Hz |
The generator above starts at 128 Hz. You can still move the slider to any other frequency, or open the full tone generator.
Questions people ask
Why can't I hear the 128 Hz tone?
Check the tab is not muted and the correct output device is selected. 128 Hz is well within the range of nearly every speaker and headphone.
How long is one cycle of 128 Hz?
7.813 milliseconds. In room-temperature air the wavelength is about 2.68 metres.
Keep testing
- Tone generatorSine, square, triangle and sawtooth from 1 Hz to 22 kHz.
- Frequency sweepLogarithmic or linear sweeps over any range and duration.
- Speaker testChannel, range and polarity checks for stereo speakers.