Happy 200th Édouard-Léon Scott de Martinville
Two hundred years ago, a Frenchman was born. According to history, his primary aim wasn't to record sound for the purpose of playback. He actually just wanted to visually understand the nature of sound, he wanted to know what sound looked like. From NPR yesterday:
"The idea of playback just didn't occur to him" says Emily Thompson, a professor at Princeton who teaches the history of sound technology. "He wanted to understand how sounds worked. He's part of a tradition of finding ways to render sound visible so that you could look at it and learn about it."
In Scott's pursuit to see sound, he inadvertently beat Thomas Edison's efforts to record sound by about twenty years. While Scott's phonautograph was the first invention to ever record sound, Edison's phonograph was the first to be able to play it back.
Experiencing sound across mediums, frequently transcending time and space, is ubiquitous in most parts of the world these days. I think we forget how spectacular of an achievement it is. A quick physics refresher to remind us all of how amazing our nearly effortless abilities to play music on demand, listen to podcasts whenever we want, amplify sound in the middle of a forest, or record a friend playing an instrument in our living room and stream it live:
- Sound is a vibration, typically involving a wave oscillating and displacing through a medium. That medium is usually air but waves can travel through lots of kinds of substances, like whale sounds underwater, for example.
- We humans can hear sound waves with frequencies between about 20 Hz and 20 kHz.
- The basic parameters to describe a wave's energy:
- frequency (speed/wavelength)
- wavelength (the longer the wavelength, the lower the pitch)
- speed (343m/sec at standard temperature and pressure)
- amplitude (greater amplitude mean louder sound)
- The wavelength of human voice is about a meter long
And this is to say/share nothing about human physiology and psychology of how we perceive sound nor the specific science of acoustics. Click the links to properly nerd out. Shoutout to Wikipedia. You can support them here.