Good Vibrations
Our ears are amazing little marvels of engineering.

One day, I was standing in front of a copier. I was testing to make sure my settings were right, so I only made one copy. Everything looked good. I pressed 25 to make the full run and hit copy.

The machine exploded.

Given the sheer volume of noise—metal screeching against metal in a banshee-like cry—I was sure it would never make little replicates again.

In about five seconds, I realized two things: 1) The copier was still behaving normally, churning out perfect print as though the world were not ending. 2) The sound was not coming from the copier at all. Someone had started a shredder on the other side of the room at the same moment I pushed the button.

Earlier that day, my car had made a metallic rattle. This was nothing new. When I turned, I would hear a click, probably a U-joint or an axle—something wrong. But this rattle was different. I listened, not really sure what was causing it. When the car stopped, the rattle stopped with it. I looked around and saw a can in the drink holder. I reached out and gave it a whap. The resulting sound was nothing like the rattle I had heard before—the volume was much softer, and it didn’t sound as frantic—but the pitch and the timbre (more on these terms later) were the same as the louder rattle. The original rattle was the can bouncing around in the cup holder. You can often tell a lot about what is going on around you by noting the sound of it, even if your spatial perception is as lousy as mine.

Our ears are amazing little marvels of engineering. They contain many tiny mechanisms that work together to turn sound waves into signals that can be translated by our brains into a form that we can understand—like words, or music, or the clicking of the keys as I’m typing right now.

The ear is divided into three general sections: the outer ear, the middle ear and the inner ear.

The outer part of your ear is called the pinna or auricle. This is the part of the ear that is visible on the outside of your head. Its main job is to gather the sounds that occur around you, from a friend’s quiet whisper to the loud honking of a car horn.

The outer ear also contains the ear canal, which is where your earwax is produced. Earwax may seem gross and unnecessary, but it has an important purpose: It protects the ear canal by containing chemicals that fight off ear infections, and it also collects dirt to keep your ear canal clean. So it is gross—but it’s gross for a reason.

The middle part of your ear turns the sound waves collected by the outer ear into vibrations that are sent into the inner ear. The eardrum performs this important job. It is a paper-thin piece of skin stretched very tightly across the end of your ear canal. When sound waves travel down the ear canal toward the middle ear and hit the eardrum, the eardrum vibrates—just as a snare drum vibrates when it is hit by a drumstick. The vibration of the eardrum causes the ossicles to move as well. The ossicles are the three tiniest and most delicate bones in your body: the malleus, the incus and the stapes. The movement of these three tiny bones helps transfer the sound toward the inner ear.

Next, the sound waves reach the inner ear and enter the cochlea. The cochlea is a tiny, curled tube in your inner ear that is shaped kind of like a snail. This snail-like organ is filled with fluid and is lined with microscopic cells covered in even more microscopic hairs. Each of your ears has about 18,000 of these hair cells. Together, these hair cells could all fit on the head of a pin. These hair cells are incredibly tiny.

The sound waves vibrate the fluid inside the cochlea, and that moves the tiny hairs on the cells lining the cochlea’s walls. This creates nerve signals, which are sent along the auditory nerve to the brain, where the signals are translated into sounds and words that your brain can understand. And this entire process—from the moment your friend says “Boo!” until your brain registers that you have been scared—happens in the merest fraction of a second.

The hair cells in your cochlea are incredibly delicate. If we aren’t careful to protect our ears from sounds that are too loud, we can do irreparable damage to these microscopic hair cells. Sound makes the hairs vibrate and move back and forth. If sounds are too loud—like a loud rock concert or a piece of really loud machinery—those hairs can bend or even break, and the hair cell will die, never sending signals to the brain again. Once a hair cell dies, it never grows back. This is how people experience hearing loss.

So how does all this translate into what you actually hear? Let’s say you go to a piano and play an A. Three things will make up the sound you here: pitch, timbre and volume (or what science nerds call loudness).

First is the note you are hearing—the pitch. I’ll assume you played the A above middle C (unless you are a 7-year-old, in which case, you ran up and down the piano playing them all). That A above middle C is exactly 440 hertz—its frequency (the frequency is the rate of vibration in the sound wave). If we double the frequency, we get a note twice as high—still an A, but the next one up on the piano: 880 hertz.

That doubling principle can be easily demonstrated with a guitar too. Pluck an open string, and you’ll hear a note. Press halfway down the string, and you’ll get a note exactly twice as high. A string twice as long would produce a note twice as low.

That guitar doesn’t sound the same as the piano though—even if you play the same note with the same frequency. And the exact same note on a clarinet or a cello would also have a totally different quality—and that difference is called timbre. Before you try to fell any trees, timbre rhymes with amber. Timbre is why you can tell the difference between a flute and a viola, or between your mom’s and your dad’s voice saying “Hello” when you call home.

When you hear a lawn mower, you are really hearing different pitches at different timbres. You’ve probably never stopped to note exactly what you are hearing, but however cacophonous the sound is, it is still comprised of pitches at distinct timbres.

Combine the pitch and the timbre with its distinct loudness, and you have everything you need to create sounds from the softest whisper to the most piercing shout, whether from an under-nourished fly or a 200-voice choir.

Imagine living life without ever being able to hear a single sound. What would that be like? Sadly, there are many deaf people who have never been able to hear as we can. But in the soon-coming world, “… [T]he ears of the deaf will be unstopped” (Isaiah 35:5), and they will be able to hear and enjoy the sounds of the world around us as God intended.

Mr. Armstrong wrote in The Missing Dimension in Sex that “the largest, most complicated machines man has designed pale to insignificance beside the most wonderful of all mechanisms—the human body and mind! This awe-inspiring mechanism … was the supreme masterpiece of God’s creative handiwork!” Every part of us was created for a beautiful purpose, and the intricacies of the human ear show the detailed thought our Creator God put into every part of His creation.

So the next time you listen to the sound of an exquisite string quartet, or the sound of a child’s carefree laugh, or the sound of a sparkling water can rattling around in your cup holder, remember the marvelous creation inside your ears. Perhaps studying these marvels of creation will lead us to respond as David did in Psalm 139:14: “I will praise thee, for I am fearfully and wonderfully made.”