The Sound Machine

The Sound Machine Sources and ClassicNote Author

By Maxwell Olson · Edited by James Cooper · Last reviewed September 28, 2020

Maxwell Olson, author of ClassicNote. Completed on September 22, 2020, copyright held by GradeSaver.
Updated and revised by James Cooper September 28, 2020. Copyright held by GradeSaver.
Roald Dahl. The Sound Machine. London: Penguin Books, 2012.
"About Roald Dahl." Roald Dahl Official Website. 18 September 2020. <https://www.roalddahl.com/roald-dahl>.
"The Audible Spectrum." NCBI. 21 September 2020. <https://www.ncbi.nlm.nih.gov/books/NBK10924/#:~:text=Humans%20can%20detect%20sounds%20in,to%2015%E2%80%9317%20kHz.)>.
"Researchers design sounds that can be recorded by microphones but inaudible to humans." Phys.Org. 23 June 2017. 22 September 2020. <https://phys.org/news/2017-06-microphones-inaudible-humans.html>.