Text
Koenig, Rudolph. 1864. “Beirag Zur “Theorie Der Klangfiguren Von Wheatstone””. Annalen Der Physik Und Chemie 122: 238-242.
Object, Instrument, Technology

Date of production: 1950s

Image
“Brüel & Kjær 2304 Level Recorder (1)”. n.d.
Image
“Brüel & Kjær 2304 Level Recorder (2)”. n.d.
Video
Braguinski, Nikita. 2018. Brüel & Kjær 2304 Level Recorder (Video).
Video
Chladni, Ernst Florens Friedrich. 2012. “Chladni Plate Demonstration From The National Museum Of American History”. Smithsonian National Museum of American History. https://youtu.be/KEttRmu2kGk.
Object, Instrument, Technology

The German scientist Ernst Chladni was one of the pioneers of experimental acoustics. His research on different kinds of vibrations served as the basis for the scientific understanding of sound that later emerged in the 19th century. 

Object, Instrument, Technology

In its simplest form the siren consists of two metal disks, each having the same number of regularly spaced concentric holes. The lower disk is mounted on the base of the siren, while the upper disk is mounted on a steel shaft just above it. As air is forced through the system, the upper disk begins to rotate. As it spins, the holes in the two disks briefly line up and then quickly close. Each time they do this, a brief puff of air is released. Each of these puffs acts like a single sound wave, and if enough of them are produced we perceive them as a continuous musical sound.

Text
Chladni, Ernst Florens Friedrich. 1830. Die Akustik. Leipzig: Breitkopf und Härtel.
Object, Instrument, Technology

The sound synthesiser was Helmholtz’s clearest instrumental expression of his theory of timbre, or sound quality. Whereas his spherical resonators dissected compound sounds (vowels or musical sounds) into elemental frequencies, the synthesiser did this by building up complex sounds from simple frequencies. In 1857 he went to the instrument maker Friedrich Fessel of Cologne to turn this idea into reality. The initial instruments used a combination of electrically driven tuning forks, resonators and piano keys to synthesise compound sounds.