The icophone is an instrument of

speech synthesis Speech synthesis is the artificial production of human speech. A computer system used for this purpose is called a speech synthesizer, and can be implemented in software or hardware products. A text-to-speech (TTS) system converts normal langua ...

conceived by Émile Leipp in 1964 and used for synthesizing the

French language French ( or ) is a Romance languages, Romance language of the Indo-European languages, Indo-European family. Like all other Romance languages, it descended from the Vulgar Latin of the Roman Empire. French evolved from Northern Old Gallo-R ...

. The two first icophones were made in the laboratory of physical mechanics of

Saint-Cyr-l'École Saint-Cyr-l'École () is a Communes of France, commune in the western suburbs of Paris, France. It is located from the Kilometre zero, centre of Paris. It used to host the training school for officers of the French army, the École spéciale mil ...

. The principle of the icophone is the representation of the sound by a

spectrograph An optical spectrometer (spectrophotometer, spectrograph or spectroscope) is an instrument used to measure properties of light over a specific portion of the electromagnetic spectrum, typically used in spectroscopic analysis to identify mate ...

. The

spectrogram A spectrogram is a visual representation of the spectrum of frequencies of a signal as it varies with time. When applied to an audio signal, spectrograms are sometimes called sonographs, voiceprints, or voicegrams. When the data are represen ...

analyzes a word, a phrase, or more generally a sound, and shows the distribution of the different frequencies with their relative intensities. The first machines to synthesize words were made by displaying the form of the spectrogram on a transparent tape, which controls a series of

oscillators Oscillation is the repetitive or periodic variation, typically in time, of some measure about a central value (often a point of equilibrium) or between two or more different states. Familiar examples of oscillation include a swinging pendulum ...

following the presence or absence of a black mark on the tape. Leipp succeeded in decomposing the segments of a spoken sound phenomenon, and in synthesizing them from a very simplified display..

References

{{reflist Acoustics Signal processing Time–frequency analysis