Sound

Sound is a vibration that propagates as an acoustic wave, through a transmission medium such as a gas, liquid or solid.

Humans can hear sound frequencies between 20 Hz to 20 kHz.
Sound waves with frequency above 20 kHz are called ultrasound waves. Sound waves with frequency below 20 Hz are called infra-sound waves.
Human beings cannot hear ultrasound waves and infra-sound waves, but some animals, like bats and dolphins, use them.
People are best at hearing sounds between 1000 Hz and 6000 Hz.

Links

The case for listening to complete discographies

By Colin Marshall, posted October 27, 2022
https://newyorker.com/culture/cultural-comment/the-case-for-listening-to-complete-discographies
In a world of obscene musical abundance, a listener needs a strategy
Now that music flows “like water,” Spotify in particular has become something like a utility. Not only does the service make it easy to listen to entire discographies, its overwhelming abundance of music practically necessitates such a rigorous practice. That abundance is one vector of the boredom that Reynolds diagnoses as particular to cultural life in the twenty-first century, which furnishes us with “a thousand TV channels, the bounty of Netflix, countless net radio stations, innumerable unlistened-to albums, unwatched DVDs and unread books, the maze-like anarchive of YouTube. Today’s boredom is not hungry, a response to deprivation; it is a loss of cultural appetite, in response to the surfeit of claims on your attention and time.” To listen through the work of one artist, never skipping an album, is to (as Reynolds writes of a music-journalist friend who restricted himself to downloading and listening to one MP3 at a time) build "a filter, or perhaps a dam, to protect against the rising sea levels of the ocean of sound.

‘There’s endless choice, but you’re not listening’: fans quitting Spotify to save their love of music

By Liz Pelly, posted Tue 27 Sep 2022
https://theguardian.com/music/2022/sep/27/theres-endless-choice-but-youre-not-listening-fans-quitting-spotify-to-save-their-love-of-music
Former streaming service subscribers on why they have ditched mod cons for MP3s, CDs and other DIY music formats
“With streaming, things were starting to become quite throwaway and disposable,” says Finlay Shakespeare. A Bristol-based musician and audio engineer, Shakespeare recently deleted his streaming accounts and bought a used iPod on eBay for £40. With streaming, he says: “If I didn’t gel with an album or an artist’s work at first, I tended not to go back to it.” But he realised that a lot of his all-time favourite albums were ones that grew on him over time. “Streaming was actually contributing to some degree of dismissal of new music.” Even with digital downloads, he tended to give music more time and attention.
“Streaming makes the listening experience much more passive,” he continues. “The word ‘streaming’ is one of those things that’s gradually assimilated into everyone’s vocabulary. Before there was streaming music, what else was streaming? This idea that you can just turn on a faucet, and out comes music. It’s something that leaves everyone to take it for granted”
“Taking the extra step to load it on to my phone, or the extra step to flip over the tape, or put the CD on in the car, it feels like something that I’m doing, rather than something I’m receiving,” they continue. “And that sense of agency makes me a more dedicated and involved listener than the kind of passive listening-without-listening that streaming was making me do”
Lethem reported something similar: she now listens mostly to records, Bandcamp downloads, and a little radio she put in her kitchen. “The choices are very limited. But it’s actually freeing. [With streaming] there’s endless accessibility, but you’re not really listening to anything. At least that’s what it started feeling like to me. I’m experiencing so much music, but am I really listening to any of it?”

Sasers: Sound-based lasers invented

Published June 17, 2009
https://livescience.com/3705-sasers-sound-based-lasers-invented.html
https://wikipedia.org/wiki/Sound\_amplification\_by\_stimulated\_emission\_of\_radiation
Scientists have created what they call a “saser,” the sound-based equivalent of a laser
A saser uses sound waves composed of sonic vibrations called phonons
A saser produces an intense beam of uniform sound waves on a nano scale, scientists say. The new device could have significant and useful applications in the worlds of computing, imaging and even anti-terrorist security screening.

Scientists develop saser–an acoustic laser–that produces terahertz sound waves

By Gail Overton, published June 19, 2009
https://laserfocusworld.com/test-measurement/research/article/16566273/scientists-develop-saseran-acoustic-laserthat-produces-terahertz-sound-waves
Scientists at The University of Nottingham, in collaboration with colleagues in the Ukraine, have produced an acoustic laser device called a saser that is the first to emit in the terahertz range
While a laser (Light Amplification by the Stimulated Emission of Radiation) uses packets of electromagnetic vibrations called photons, the saser uses sound waves composed of sonic vibrations called phonons
A key factor in this new science is that the saser is the first device to emit sound waves in the terahertz frequency range. One example of its potential is as a sonogram, to look for defects in nanometer-scale objects like micro-electric circuits. Another idea is to convert the saser beam to THz electromagnetic waves for medical imaging and security screening.

Good vibrations - the healing power of sound-baths

Why a ‘lying-down concert’ is key to the new wellness frontier
By Rebecca Newman, posted August 23 2022
https://ft.com/content/9cdb0914-8c26-4fb6-bbbe-58b875f600c5

Stonehenge bluestones had acoustic properties, study shows

Published 3 March 2014
https://bbc.com/news/uk-england-wiltshire-26417976
The giant bluestones of Stonehenge may have been chosen because of their acoustic properties, claim researchers

The Acoustics of Stonehenge: Researchers build a model to understand how sound reverberated within the ancient structure

Published 28 June 2021
https://openculture.com/2021/06/the-acoustics-of-stonehenge.html

Sonic geometry

https://sonicgeometry.com

The Language of Frequency & Form
Communicating with the Universe
A Message to the Citizens of Earth

Why we stop discovering new music at age 30

By Lindsay Dodgson, posted Jun 7, 2018
https://businessinsider.com/why-we-stop-discovering-new-music-around-age-30-2018-6

A new survey from Deezer suggests we stop listening to new music at age 30
The results put this down to a busy life
But there could be other reasons, like the fact we don’t soak up new music in the same way anymore
For example, between 12 and 22 our brains go through a lot of changes and we’re more receptive to the songs we hear
Whatever the reason, our brains like nostalgic music, and there’s no shame in indulging them