By: Mayten Lumpkin

In 1857, Édouard-Léon Scott de Martinville invented the phonautograph, the first device that could record sound waves as they passed through the air. It was intended only for visual study of the recording and could not play back the sound. The recording medium was a sheet of soot-coated paper wrapped around a rotating cylinder carried on a threaded rod. A stylus, attached to a diaphragm through a series of levers, traced a line through the soot, creating a graphic record of the motions of the diaphragm as it was minutely propelled back and forth by the audio-frequency variations in air pressure.

 Modern headphones are indispensable accessories for private audio transmission at home, in the office, or on the go. Headphones are especially prominent equipment among carriers of laptops, cell phones, analogue and digital music players, audio recorders, and many other personal electronic devices. Perhaps no other headphone in history has gained more attention than the fashionably white ear bud-style headphones made popular by Apple’s now virtually ubiquitous iPod. But headphones were not always a technology readily available for general use. The individual components of headphones are technological innovations that are vital to modern electronics for many more uses beyond the transmission of sound.  Headphones, in other words, while taken for granted today—from inexpensive versions packaged with electronic devices to the highest quality models—are achievements in human invention that coincide with other critical innovations without which headphones as we know them would not be possible. Like many histories of modern invention in physics and electronics, the history of headphones has roots in the experimentation of Thomas Edison. Though he did not know it at the time, some of his work with electrical currents indirectly led to innovations that made possible the amplification of audio signals.

 1877 Thomas Alva Edison, working in his lab, succeeds in recovering Mary's Little Lamb from a strip of tinfoil wrapped around a spinning cylinder.  He demonstrates his invention in the offices of Scientific American, and the phonograph is born.

 1878 The first music is put on record: cornetist Jules Levy plays "Yankee Doodle."

 1881 Clement Ader, using carbon microphones and armature headphones, accidentally produces a stereo effect when listeners outside the hall monitor adjacent telephone lines linked to stage mikes at the Paris Opera.

 1887 Emile Berliner is granted a patent on a flat-disc gramophone, making the production of multiple copies practical.

 1888 Edison introduces an electric motor- driven phonograph.

 1895 Marconi successfully experiments with his wireless telegraphy system in Italy, leading to the first transatlantic signals from Poldhu, Cornwall, UK to St. John's, Newfoundland in 1901.

 1898 Valdemar Poulsen patents his "Telegraphone," recording magnetically on steel wire

 1900 Poulsen unveils his invention to the public at the Paris Exposition. Austria's Emperor Franz Josef records his congratulations.  Boston's Symphony Hall opens with the benefit of Wallace Clement Sabine's acoustical advice.

 1901 The Victor Talking Machine Company is founded by Emile Berliner and Eldridge Johnson.  Experimental optical recordings are made on motion picture film.

 1906 Lee Deforest invents the triode vacuum tube, the first electronic signal amplifier.

 1910 Enrico Caruso is heard in the first live broadcast from the Metropolitan Opera, NYC.

 1912 Major Edwin F. Armstrong is issued a patent for a regenerative circuit, making radio reception practical

 1913 The first "talking movie" is demonstrated by Edison using his Kinetophone process, a cylinder player mechanically synchronized to a film projector

 1916 A patent for the superheterodyne circuit is issued to Armstrong.  The Society of Motion Picture Engineers (SMPE) is formed.  Edison does live-versus-recorded demonstrations in Carnegie Hall, NYC.

 1917 The Scully disk recording lathe is introduced.  E. C. Wente of Bell Telephone Laboratories publishes a paper in Physical Review describing a "uniformly sensitive instrument for the absolute measurement of sound intensity" -- the condenser microphone.

 1919 The Radio Corporation of America (RCA) is founded. It is owned in part by United Fruit.

1921 The first commercial AM radio broadcast is made by KDKA, Pittsburgh PA.

 1925 Bell Labs develops a moving armature lateral cutting system for electrical recording on disk. Concurrently they Introduce the Victor Orthophonic Victrola, "Credenza" model. This all-acoustic player -- with no electronics -- is considered a leap forward in phonograph design.  The first electrically recorded 78 rpm disks appear.  RCA works on the development of ribbon microphones.

 1926 O'Neill patents iron oxide-coated paper tape

 1927 "The Jazz Singer" is released as the first commercial talking picture, using Vitaphone sound on disks synchronized with film.  The Columbia Broadcasting System (CBS) is formed.  The Japan Victor Corporation (JVC) is formed as a subsidiary of the Victor Talking Machine Co.

 1928 Dr. Harold Black at Bell Labs applies for a patent on the principle of negative feedback. It is granted nine years later.  Dr. Georg Neumann founds a company in Germany to manufacture his condenser microphones. Its first product is the Model CMV 3.

 1929 Harry Nyquist publishes the mathematical foundation for the sampling theorem basic to all digital audio processing, the "Nyquist Theorem."  The "Blattnerphone" is developed for use as a magnetic recorder using steel tape.

 1931 Alan Blumlein, working for Electrical and Musical Industries (EMI) in London, in effect patents stereo. His seminal patent discusses the theory of stereo, both describing and picturing in the course of its 70-odd individual claims a coincident crossed-eights miking arrangement and a "45-45" cutting system for stereo disks.  Arthur Keller and associates at Bell Labs in New York experiment with a vertical-lateral stereo disk cutter.

 1932 The first cardioid ribbon microphone is patented by Dr. Harry F. Olson of RCA, using a field coil instead of a permanent magnet.

 1933 Magnetic recording on steel wire is developed commercially.  Snow, Fletcher, and Steinberg at Bell Labs transmit the first inter-city stereo audio program

 1935 AEG (Germany) exhibits its "Magnetophon" Model K-1 at the Berlin Radio Exposition.  BASF prepares the first plastic-based magnetic tapes.

 1936 BASF makes the first tape recording of a symphony concert during a visit by the touring London Philharmonic Orchestra. Sir Thomas Beecham conducts Mozart.  Von Braunmühl and Weber apply for a patent on the cardioid condenser microphone

 1938 Benjamin B. Bauer of Shure Bros. engineers a single microphone element to produce a cardioid pickup pattern, called the Unidyne, Model 55. This later becomes the basis for the well known SM57 and SM58 microphones.  Under the direction of Dr. Harry Olson, Leslie J. Anderson designs the 44B ribbon bidirectional microphone and the 77B ribbon unidirectional for RCA.  RCA develops the first column loudspeaker array.

 1939 Independently, engineers in Germany, Japan and the U.S. discover and develop AC biasing for magnetic recording.  Western Electric designs the first motional feedback, vertical-cut disk recording head.  Major Armstrong, the inventor of FM radio, makes the first experimental FM broadcast.  The first of many attempts is made to define a standard for the VU meter.