Elisha Gray and the Harmonic Telegraph

In 1874 Elisha Gray discovered that his nephew had built by accident an electric circuit that produced a sound. Gray reproduced the experiment and developed the principle of self vibrating electromagnetic devices. The first "musical telegraph" or "harmonic telegraph" was equipped with enough single-tone oscillators to play two octaves. Gray took the instrument on tour with him in 1874.

Thaddeus Cahill and the Telharmonium

Thaddeus Cahill is considered the inventor of the first serious musical electronic instrument. His 1896 patent described a device with electrical tone generating devices, dynamics-controlling devices for building tones, a keyboard for activating the tone-generating circuitry, and a loud-speaker.
Cahill was able to use the telharmonium to imitate common orchestral instruments like the oboe, cello or violin.

The first large telharmonium was gigantic, it occupied the better part of the factory it was located in. The entire instrument weighed about 200 tons.

William Duddell and his Singing Arc

By the year 1900, in London, streetlights generated light using an electric arc which produced an annoying whining sound. Physicist William Duddell was trying to devise a way to eliminate this sound and found a way to control its frequency! He attached a keyboard to his first voltage-controlled device and took the instrument on tour.

The "Singing Arc" became a novelty by the turn of the century.

The Theremin

The Theremin is the invention of the Russian scientist Leon Theremin. This instrument was first built in Russia in 1920 but it actually gained audience around 1928.

The technical principle of the theremin is a phenomenon known as heterodyning: when you mix two signals with two slightly different frequencies the resulting signal has a frequency equal to the difference of the two frequencies.

The great idea of Leon Theremin consists in using a reference high frequency oscillator and a variable high frequency oscillator: the resulting low frequency varies as the variable high frequency oscillator varies. The variation of the variable oscillator is due to the position of the Theremin player body between two antennae.

The Theremin, thanks to its original controllers has survived 70 years of technical evolution: a transistorized version of the Theremin is still available today from Big Briar, Inc. (see Manufacturers).

The sound of the Theremin is known as a source for sound effects in movies such as "The Day the Earth Stood Still" Leon Theremin died in Moscow in November 1993 at the age of 97.

The Hammond Organ

The Hammond organ was designed in the thirties. From a technological point of view, it is a miniature version of the Telharmonium. It weighs 200 kg instead of 200 tons. Its sound generators are known as phonic wheels. A "cog" wheel is rotating in front of an electromagnet. As the metallic surface ("cogs") in front of the electromagnet varies, it generates an electric current in the wire. This signal is then amplified by triode lamps.

Thanks to its weight it was and is still used by musicians on tour. The jazz and rock musics uses this instrument extensively. The commercial success of the Hammond organ is due to its price: it is as affordable as a piano but allows the player to play jazz and rock at home.

The Moog Synthesizer

While getting his doctorate in physics in 1963, Robert Moog made money by selling do-it-yourself transistorized theremins. One of Moog's transistorized thereminists was Herbert Deutsch, a composer. Moog and Deutsch met in 1963 at a conference. This led to conversation about the need for new electronic instruments. Moog had his very first prototype built in August 1964.

The principle of his prototype was the use of voltage controlled generators and filters. This allows the performer to create their own sounds by connecting modules with electric wires and by turning knobs. In 1968 a recording of Bach's music called "Switched On Bach" was performed by Walter Carlos.

Thanks to this musical success, Moog designed other synthesizers such as the Moog System 55. The most popular of Moog's synthesizer is known as the Minimoog.

Read the Bob Moog interview here

The Beauchamp synthesizer

Additive synthesis is the most intuitive of synthesis methods: you make a sound by adding elementary sine signals which frequencies and amplitudes evolve.
Beauchamp's additive synthesizer was able to generate six harmonics each with their own amplitude envelop. Furthermore, the phase-shift of the second harmonic was voltage controlled.

As every part of this synthesizer was voltage controlled, it was possible to use it with other modules to achieve a composite synthesis method (additive, subtractive and modulation synthesis).

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