Audiograms test pure-tone detection because pure tones are maximally frequency-specific

Evidence

The pure tone is one of the most basic forms of sound and, importantly, is the foundation of a typical audiometric assessment in the form of the audiogram, a report of the ability to detect pure tones as a function of frequency. Pure tones are preferred for audiometric testing over other sounds (such as noises or modulated sounds) as they contain a single frequency and therefore are the most frequency-specific sounds. A single parameter is sufficient to fully characterize the amplitude or sound pressure of the tone. Of all potential stimuli, the pure tone is acoustically very simple, and produces a relatively simple response in the auditory system. — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 161

Categorization

• DEFINE: Explains what an audiogram is and why pure tones anchor audiometry, core background for the reader’s audiology-oriented goal.
• XREF: Ties to the classic audiogram figure with the ‘speech banana’ band of conversational speech, familiar from hearing-loss literature.