A Look at the Speech Banana – Precisely What Is It?

To start with an attempt at humor, the “speech banana” isn’t a reference to that classic vaudeville skit, “Speak up…I can’t hear you…I’ve got a banana in my ear.” The “speech banana” is a specific design depicted on an audiogram. Audiograms are usually graphed with the frequency level (measured in Hertz) on one axis and volume level (measured in Decibels) on the other axis.

When the typical sounds of human speech – or phonemes – are graphed on this kind of audiogram, they have a tendency to all fall inside an area of the chart that is shaped like a banana. The spoken sound of all of the letters of the alphabet, aside from q, w, x, and y, fall inside the speech banana, as do the very widespread letter combinations ch, sh, th and ng.

People with normal hearing can also hear sounds that fall outside this speech banana range – including higher-frequency sounds such as birds chirping or leaves rustling and lower-frequency sounds such as machinery or tubas – but the sounds most vital to human communication are the sounds of other people talking. People with hearing loss frequently have difficulty hearing certain vowels and the letter combinations ng, ch, sh and th.

As a result, hearing specialist are most concerned with hearing loss that happens within the region of the speech banana. Whether the individual is young or old, if they are having difficulty hearing sounds within that frequency and volume range, they are almost definitively having difficulty hearing speech, and thus have problems communicating effectively with others.

The range of spoken sounds captured by the speech banana is so vital to communications, that many school districts mandate hearing tests using audiograms to identify hearing losses in this region. Because this frequency and volume range of sounds is so vital to human communications it is the range that most hearing aids are adjusted and programmed to perform best in. If you have any concerns about your ability to hear in the speech banana range we encourage you to call and get more information.