The Speech Banana is a visual representation used in audiograms to show the frequencies at which different speech sounds are produced, as well as common environmental sounds. It helps to illustrate the frequency range of human speech and the way sounds are perceived across different levels of hearing. The chart is often divided into categories based on hearing loss severity: Normal Hearing, Mild Hearing Loss, Moderate Hearing Loss, Severe Hearing Loss, and Profound Hearing Loss. 

Speech Sounds by Frequency 

Speech sounds found in the Speech Banana and their corresponding frequency ranges: 

  • **Low Frequencies (125 - 500 Hz):** These frequencies represent the lower tones in speech and are associated with the vowel sounds. Examples include the vowels in 'a', 'o', and 'u' (e.g., 'father' or 'food'). These sounds tend to be more audible to individuals with mild to moderate hearing loss. 

  • **Mid Frequencies (500 - 2000 Hz):** This range is where many consonants and vowels fall. Sounds like 'm', 'b', 'n', and 'd' are found here. These are important for understanding speech in everyday conversation, as they help differentiate words. 

  • **Higher Frequencies (2000 - 4000 Hz):** High-frequency consonants like 's', 'f', 'sh', and 'th' occur in this range. These sounds are crucial for understanding speech clarity, especially in distinguishing between similar words such as 'pat' and 'fat'. 

  • **Very High Frequencies (4000 - 8000 Hz):** These frequencies are often associated with environmental sounds like birds, leaves rustling, and high-pitched noises like the sound of a whistle. Some speech sounds, such as the 's' in 'socks', also exist in this range. 

Environmental Sounds by Frequency 

In addition to speech sounds, the Speech Banana also shows common environmental sounds and their respective frequency ranges: 

  • **Low-Frequency Sounds (125 - 500 Hz):** Examples of these sounds include the hum of a refrigerator, the sound of a truck, or a drum kit. These sounds tend to be perceived by individuals with moderate or normal hearing. 

  • **Mid-Frequency Sounds (500 - 2000 Hz):** Common sounds here include the sound of a vacuum cleaner, the noise of a motorcycle, or a piano playing. These sounds are often heard at higher volumes by individuals with mild hearing loss. 

  • **Higher-Frequency Sounds (2000 - 4000 Hz):** Environmental sounds such as a parrot's squawk or the rustling of leaves fit into this category. These sounds may be missed by individuals with severe to profound hearing loss. 

  • **Very High-Frequency Sounds (4000 - 8000 Hz):** These frequencies include the sound of an airplane flying overhead, the ringing of a high-pitched alarm, or the sharp whistle of a kettle.