Why Can Humans Only Hear Between 20 Hz and 20kHz?

If you’ve ever used a dog whistle before, you may have blown into the device with no sound produced at all. Except you did make a noise — it was just at a frequency level indistinguishable to the human ear. Your four-legged friend, however, likely perked up his ears the moment you blew into this seemingly unintelligible whistle.

While dogs and our other furry companions can hear frequencies reaching up to 80kHZ, we can only distinguish noises between 20 Hz and 20kHz. If that number seems low in comparison, don’t feel discouraged. Our ears are incredibly complex organs that provide us with the ability to retain and transmit vibrations into noises our brain comprehends and attaches a meaning to with ease. Pretty amazing, isn’t it?

How the Structure of Our Ear Impacts the Sound Range We Hear

Because ears are a part of our human body, it’s no wonder they’re so seemingly complicated. To make matters even more intricate, we have not one, but two, of these magical little organs. To better understand the range of human hearing, it’s essential to first understand the structure that makes our ears into the hearing devices we rely on daily.

The outer part of the ear consists of two different portions: the ear canal and the skin and cartilage that we can visibly see when we look at our ears. These parts of the ear are responsible for transferring external noises into our body. The eardrum picks up vibrations and sends them to the ear’s middle structure: the cochlea. Here, the noise waves transform into neural impulses that our brain registers as the sounds we attach meaning and significance to every time a noise is produced.

Changes in Range Over Time With Age

While the standard range of hearing for a healthy adult is between 20Hz and 20kHz, this number steadily decreases over time. For many people, the five senses undergo a steady decrease in potency with age — and hearing is no exception.

Why does hearing decrease with age? Our ears possess minuscule hair cells that help essentially “grab” sound waves that our ear later processes into intelligible sounds. Unfortunately, these small hair cells do not regrow even when they’re damaged or die. This loss of hair results in a lessened ability to hear higher frequency ranges over time.

There are various precautionary measures you can take to protect your hearing as you age. For instance, avoid extremely loud situations to prevent hearing damage earlier in life. Playing music too loudly through your earbuds, for example, can cause irrevocable damage to the inner ear that affects your ability to process higher frequency sound waves as you grow older.

Protect Your Hearing With Soundproofing Materials

The ability to process sound may seem like a given. But for those who begin to lose this capacity over time, it’s a daily sense that we often take for granted once our hearing begins to weaken.

Make sure you keep your ears healthy and in optimal working shape with soundproofing materials that protect your ears against unwanted damage. At Soundproof Cow, we provide noise reduction products that help you experience the quiet you need. For more information on our products, browse our varied selection online today or contact a representative for further assistance.