View source for Absolute Threshold of Hearing

The absolute threshold is the volume level at which one can detect a particular sound 50% of the time. If one has a low absolute threshold, it means that he is able to detect small amounts of stimulation, and thus is more sensitive. If one has a high absolute threshold, then he requires more stimulation and thus is less sensitive.

The following are curves of the ATH for several age groups over [[frequency]]. Zwicker approximated these curves from experiments on a number of subjects:
[[Image:ATH.png|frame|none|ATH graph for different age-groups]]

The ATH is the simplest property of human hearing to exploit in designing a lossy audio codec.