LSTN

Hearing Health Guide

Pure Tone Audiometry

Definition

Pure tone audiometry is the most common method of measuring hearing sensitivity. A series of pure tones, single-frequency sounds with no overtones, are played at set frequencies, typically 250 Hz through 8,000 Hz, and the volume is raised and lowered until the softest audible level (the threshold) is found at each one. The result for each ear is plotted on an audiogram, the standard chart audiologists use to describe the type and degree of hearing loss.

How the Test Works

Tones are typically delivered through headphones (air conduction), one frequency and one ear at a time. Using a standardized procedure, most often the modified Hughson-Westlake method, the volume steps down until the tone is no longer heard, then back up until it's detected again, narrowing in on the true threshold.

A full clinical test also includes bone conduction testing, where a small vibrating device placed behind the ear sends sound directly to the inner ear, bypassing the outer and middle ear. Comparing air and bone conduction results tells the audiologist whether a loss is sensorineural, conductive, or mixed.

What It Measures, and What It Doesn't

Pure tone audiometry measures threshold sensitivity: the quietest sound a person can detect at each pitch. It doesn't measure how well someone understands speech, especially in background noise, which is a separate skill tested with word recognition or speech-in-noise testing.

Two people can have identical pure-tone results and very different real-world experiences. Someone with mild high-frequency loss might follow conversation easily in a quiet room but struggle badly in a noisy restaurant, a distinction pure tone testing alone doesn't capture.

Pure Tone Audiometry vs. an Online Screening

A full clinical pure tone audiometry exam, done by an audiologist in a sound-treated booth, tests air and bone conduction across a wide frequency range with calibrated equipment. LSTN's Hearing Test uses BPTA (Bayesian Pure Tone Audiometry), an adaptive, algorithm-driven version of the same underlying method, delivered through headphones over the web to screen air conduction thresholds from 500 Hz to 4,000 Hz in about ten seconds.

It's a useful starting point for noticing a possible problem, not a replacement for a full clinical exam, which adds bone conduction, a wider frequency range, and a controlled testing environment.

Common Questions

Pure Tone Audiometry FAQ

Does pure tone audiometry hurt?
No. The test involves listening for soft beeping tones and pressing a button or raising a hand when you hear one. It's entirely non-invasive and takes about 15-30 minutes for a full clinical exam.
What frequencies are tested in pure tone audiometry?
A standard clinical test covers 250, 500, 1,000, 2,000, 3,000, 4,000, 6,000, and 8,000 Hz for air conduction, with bone conduction typically tested from 500 to 4,000 Hz.
Is an online hearing screening the same as pure tone audiometry?
It's based on the same principle, measuring thresholds at set frequencies, but an online screening like LSTN's Hearing Test tests air conduction only over a narrower frequency range and isn't a substitute for a full clinical exam with bone conduction and a controlled sound environment.