The devices with direct sound recording and playback include the means
of mechanical, optical and magnetic recording. The recording of human
voice was possible due to the invention of the phonograph by Thomas
Alva Edison in 1877 (licensed on 15 February 1878). The words "Mary
had a little lamb” uttered by Edison, stored and reproduced
on a cylinder covered with tin plate, were the testimony of this impressive
technical achievement. Preoccupations for sound recording following
the principle of the phonograph existed before Edison. Thus, Leon
Scott made in 1857 the FPHNOAUTOGRAPH, and Charles Cros in 1877 achieved
the PALÉOPHONE system. These devices though did not show any
practical application.
In 1885 Chichester Bell and Clarles
Tainter invented a type of phonograph named GRAPHOPHONE, which was
licenced on 4 May 1886. They use as a recording and playback support
the wax cylinder replacing the tin cylinder used by Edison.
Phonographs are made of an amplifying funnel at whose end there is
an elastic membrane to whom is connected the needle with the point
supported on the wax cylinder. The cylinder is rotated with a constant
speed by an arch engine. The vibration of the membrane determines
the perpendicular movement of the needle on the wax cylinder, creating
a helicoid groove with
various depths according to the intensity of the sound. The playback
was achieved by the simple movement of the needle through the groove
incised on the cylinder. The membrane oscillates following the various
depths of the groove and produces variations of the air, similar to
those which produced the recording.
In 1887 Emil Berliner obtained a license
for the gramophone, a device with crank which used for the playback
a disk and assured the recording by the vibrations of the needle which
incised side grooves of constant depth. Starting from 1888 Berliner
produces, by galvanoplastics, the multiplication of ebonite disks
from moulds with the master record.
At the beginning of the 20th century,
the gramophones gets improved. The funnel for the sound amplification
is replaced by a resonance box. These devices are known in Romania
as patephones. They enjoyed a large dissemination and showed a rich
constructive variety. Famous companies such as Victor Talking Machine,
The Gramophone Company, Pathé, Odeon, RCA Victor produced devices
which assured the delight and entertained the generations of the first
decades of the 20th century.
The birth of cinematography on 28 December
1895 represented a new means of communication and amusement which
evolved quite fast. Since it first appeared until 1927, film was mute,
while numerous attempts were done to assure the sound. In 1910 Léon
Gaumont produces the CRONOPHONE, which though was not disseminated.
Starting from 1910, Eugène Lauste assured the sound recording
on cinematographic film using the optical method. The improvement
of the optical method led to the sound movie and the premiere of the
movie "The Jazz Singer" took place on 6 October 1927 in
New York. The sound movie provided cinematography with the status
of art.
The magnetic recording of sound was experienced
for the first time by the Danish physicist Valdemar Poulsen in 1898.
The device made by V. Poulsen, entitled TELEGRAPHONE was licensed
in the U.S.A. on 21 April 1900 and was destined to telephonic messages.
The device consisted in a bronze cylinder on which was rolled a steel
thread between two electromagnets which received current from a microphone.
The German engineer Stille replaced the steel thread with a steel
tape 3 mm wide, and in 1928 Fritz Pfleumer replaced the steel tape
with a tape of paper coated with iron oxyde. Later, this sound transmitting
tape is replaced with a polyester tape. In 1941, in U.S.A. and Germany
at the same time, the tape recorder (magnetophone) was designed, so
that the device assured the polarized and erasing by high frequency
currents. The name of magnetophone was given by the "Telefunken”
company. The technical improvements applied to the device, the invention
of transistors, integrated circuits led to a varied range of taper
recorders which became much smaller, and to the construction of a
new device named cassette player.
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