The Little Vulgar Book of Mechanics (v0.16.1) - Sound I
Last updated: April 26th 2022
Just updated this section of the book: Sound I
Sound I #
"In Space, no one can hear you scream." – ALIEN (1979), movie tagline.
This is one of those "facts" that people repeat all the time: There is no sound in space. Which is fine. It's true enough. The problem is that people will often "explain" it further, by saying it's because "sound needs an atmosphere in which to travel," which is wrong.
So let's start there: "There's no sound in Space." Yes, correct. "There is sound here on Earth." Also correct, obviously. And, using your powers of deduction, you can conclude: Therefore, sound requires... something, in order to exist.
So far so good.
Before we go on, though, let me set a rule: We do not say that sound "travels." Death metal screamers: I don't want you to think of your screams "traveling" from your mouth to the mic. There is no such traveling entity, or agent. There is no "scream" that is "traveling" from your mouth to the mic.
If you think sound "travels through the air," you're gonna be a shitty singer, engineer, and you will never understand anything. Your life will be that of failure. Do not think of sounds as things "traveling through the air."
Why? I'll explain in the following sections.
Before I close this introduction, though, let me leave you a legit definition of sound, from a badass engineer:
"Sound is an alteration in pressure, particle displacement, or particle velocity which is propagated in an elastic medium, or the surperposition of such propagated alterations. Sound is also the auditory sensation produced through the ear by the alterations described above."
– HARRY F. OLSON (1901–1982), "Music, Physics and Engineering" (1952).
Olson was a pioneering engineer extraordinaire. Born in America to Swedish immigrants, he was engineering all kinds of things from an early age: Building and flying model airplanes, building a steam engine, inventing a wood-fired-boiler-to-100-volt-DC-generator system, designing and building amateur radio transmitters, and so on and so forth.
Yeah, one of those guys.
He then went on to study electrical engineering, and to work for RCA Laboratories for almost 40 years, where he made lots of inventions as evidenced (at least partially) by the long list of patents to his name, involving microphones, loudspeakers, amplifiers, noise reduction systems, music synthesizers, sound absorbers, etc.
He also took the time to write some classic sound physics and engineering books, one of which ("Acoustical Engineering" (1957)) was used as a bible by The Grateful Dead's early sound engineering crew, for designing the whole "Wall of Sound" thing.
His definition of sound will make more sense once you read through the next sections.
Let this be your welcome to Sound I.
See the rest of the book's WIP here.