If you or someone you know has had a hearing test, you might have seen a chart like this:
Known as an audiogram, this graph (shown blank above) indicates the softest sounds someone can hear across the main speech frequencies (low, mid and high pitch sounds). Where your results fall on the audiogram reflects which speech and environmental sounds, if any, aren’t being heard well – or at all.
How do you read an audiogram?
At the top of the graph, the numbers ranging from 250 to 12,000 hertz (Hz) represent sound frequencies, from low pitch across to high pitch – similar to the keys on a piano. Most speech is within the range of 250 to 6,000Hz, with consonant sounds such as /S/, /SH/, /CH/ and /T/ among the highest frequencies and vowel sounds amid the lowest.
Along the vertical side, the hearing levels of -10 to 120 measure how loud a sound is in decibels (dB). The normal range of hearing is 20dB or lower, which generally means that the higher up the chart your results are plotted, the better your hearing.
Each ear is plotted as two separate lines on your audiogram. A cross symbol represents your left ear thresholds, while a round circle symbol represents your right ear.
Testing your hearing at different frequencies and volumes enables your audiologist to determine how loud a sound needs to be before you can hear it. For many people identified with hearing loss, assistive technology such as hearing aids can help to bridge those missing sounds.
How is an audiogram made?
An audiogram is created through the quick and non-invasive process of a hearing test. An audiologist will ask you to respond to a series of different tones within a quiet listening environment, typically using headphones or insert earphones.
Each frequency tone is first played at a volume you can easily hear, with the decibels slowly decreased and increased, a process called ‘threshold seeking’. This results in your hearing threshold established for each frequency and in both ears, to give an overall picture of your hearing ability.
Your audiologist will talk you through your results following your hearing test, including any hearing loss identified.
For people who require hearing aids, an audiogram helps the audiologist to determine which sounds can’t be heard and to ensure the hearing aids are programmed to focus on increasing the audibility of these sounds.
Hear and Say provides an array of audiology services for people of all ages, including comprehensive hearing tests, hearing aid fitting and management, tinnitus assessments and hearing implant services.