Object, Instrument, Technology

In 1868, Henri-Victor Régnault described an apparatus for determining the speed of sound, capable of accurately measuring time intervals to fractions of a second.

Object, Instrument, Technology

The Fourier analyzer, which was called by Rudolph Koenig an “Analyzer of the timbre of sounds”, is a large device (about 36 inches tall) for simultaneously observing several components of a sound.

Object, Instrument, Technology

This is a set of 16 Helmholtz resonators. Made from sections of brass that were spun on a lathe, they are wonderfully light and easy to hold. Helmholtz designed them to demonstrate his theory that all vowel and musical sounds are composed of combinations of simple, pure notes (Helmholtz’s “Theory of Timbre”). He correctly observed that musical sounds, particularly the higher tones, are often perceived as a single mass of sound.

Object, Instrument, Technology

Lord Kelvin’s harmonic synthesizer is basically Henrici’s harmonic analyzer in reverse. Originally designed as a tide predictor in 1873, the system can combine numerous component waves—in some devices, up to 64 separate components—into a single curve. It is based on the earlier pin-and-slot device, which produces simple harmonic motion with the turn of a crank.

Object, Instrument, Technology

In 1862, the German scientist Herman Helmholtz invented another important acoustic instrument, the double siren. The new instrument combined two Dove Sirens, which were positioned to face each other and coupled on the same shaft. Both sirens were also connected to the same air supply, which made it possible to produce a variety of frequencies, all of which would slide up or down the scale as the air pressure was increased or decreased.

Object, Instrument, Technology

The Smithsonian's National Museum of American History houses literally millions of objects which preserve and illustrate our nation's rich history. Among the many stories that these objects tell are the ways that Americans have learned about science. This site is designed to help students and teachers explore a unique and beautiful collection of instruments used to teach Acoustics - the science of sound. These historic instruments were designed to be engaging and to challenge students to think in new ways about the physical world.

Audio
2013. “24576_1876-469_Tone-Limit-App_1”.
Object, Instrument, Technology

Koenig’s flame analyser was, next to the sound synthesizer, one of the clearest expressions of Hermann von Helmholtz’s theory that complex sounds were made up of a spectrum of elemental or pure tones. The adjustable resonators covering a range of 65 notes from sol1 to mi5 (96–1,280 Hz), could each be rendered visible with a connection to a manometric flame capsule. The resonators were connected to a gas-filled capsule with a rubber tube. If activated, the distinctive pattern would appear in the rotating mirror.

Object, Instrument, Technology

Tone-limit apparatus, for high notes of high pitch.

Made by G. Appunn & Sons.

 

            This apparatus was designed for determining the highest vibration-frequency which is recognized by the ear as a musical tone. It consists of 31 small tuning forks, giving the diatonic scale

Audio
Kolkowski, Aleksander. 2013. “2048 Vps_1876-469_Tone-Limit-Apparatus_1”.