Decibels & perception toy

These toys are designed to show how the decibel scale fits with our logarithmic perception.

Decibels in sound

Be sure the volume is not up too high!

This section is designed to highlight the Just Noticeable Difference (JND) of sound. On clicking play, the sound level will play at roughly -14 dB in level. When you click the various dB increase buttons, they set the gain to the requested amount above the base gain level of -14 dB. They are not cumulative, clicking each button resets the level to the requested amount above base only. Use the slider to set a custom increase level if desired. Clicking play again will reset to -14 dB.

Use the buttons to find what you think is the JND and doubling point of sound is. Typically people find 1 dB to be the JND and 10 dB to be the doubling point, although with pink noise this might not track exactly (it changes with frequency!).

Custom gain value:

Decibels in numerical perception

Similarly to sound, your perception of numbers of objects on a screen is logarithmic. In this toy, click the "dots start" buttons to set the base level of dots. The increase buttons then increase that number by the decibel amounts shown. The natural numbers are shown below each box to show you the actual numbers of dots in each box.

You might see that the JND is around 1 dB of increase in the dots, regardless how many there are initially in the first box. Experiment to see what you think a perceptual doubling is too!

Custom increase: