Pressure Waves, Ear Drum, and the Hammer, Anvil, and Stirrup of Your Inner Ear

As a result, spherical pulses—pressure waves—of air particles radiate outward in all directions from the flexing guitar body. Really fast. These pulses—not the air itself!—move through the atmosphere at 743 miles an hour, the speed of sound. (In Canada, that’s 1,188 km per hour, which seems faster than in America, probably because of the cold, crisp Canadian air.)
The tone travels as a pressure wave through the air until it hits your ear drum. At that point, it transmogrifies into mechanical motion, setting your ear drum vibrating, just like the diaphragm inside a microphone.
And then those three teeny bones in your middle ear get into the act. Remember the “hammer, anvil, and stirrup” from elementary or middle school? Smallest bones in your body.
Finally, your inner ear transduces the vibrations into nerve impulses. The nerve impulses then travel to a number of different parts of the brain, each specialized to analyse a specific element of the sound, some related to pitch (tones, intervals, chords), some to time (beat, pulse, tempo meter, rhythm).