A tiny band in your ears: how do headphones actually work?
Have you ever wondered how those tiny speakers lodged in your ear canal create such crystal-clear sound, delivering your favourite tunes straight to the pituitary gland to release those all-important endorphins? It might seem like a feat of magic or divine intervention, but in reality, we have centuries of sonic experimentation and invention to thank for humble headphones.
Although the Walkman didn’t arrive until the late 1970s, headphone technology dates back to the late 19th century. The earliest devices offered a hands-free alternative to the telephone receiver in busy office spaces. This was especially useful in the days when switchboard operators had to communicate with those placing calls while making changes on the switchboard.
The first proper headphones, as we know them today, were invented by Nathaniel Baldwin in 1910. He crafted the very first pair in his kitchen and sold them to the US Navy, who saw the potential for military applications. As with any rudimentary design, these early models were large and uncomfortable, operating with just one earpiece.
Headphones didn’t become popular among the general public and, crucially, in recording studios until the 1950s and ’60s. Sony’s invention of the Walkman in 1979 revolutionised headphone use, making portable music a staple in everyday life. Since then, headphone technology has continued to evolve, incorporating new features and improving sound quality.
Regular headphones work in a similar way to standard speakers, but the entire operation is scaled down for an acute, in-ear listening experience. The driver unit, which consists of a diaphragm, a magnet, and a coil, sits protected within the ergonomically designed cups (or buds for earphones).
The magnet and coil receive the electric impulses from the record player, MP3 player or guitar amp, which incites a varying magnetic field that changes with the nature of the sonic information. The variation in the magnetic field moves the diaphragm accordingly, vibrating the air particles that exert pressure on the eardrums.
How do noise-cancelling headphones work?
Over the years, headphone and earphone technology has come on in leaps and bounds. Many people today enjoy wireless connection using Bluetooth technology, often coupled with noise-cancelling innovation.
Noise-cancelling headphones use built-in microphones to pick up external, ambient sounds and produce inverse sound waves to cancel them out in the mix delivered to your ears.
