How did home audio evolve after World War II - from magnetic recording to new speakers
Photo dom christie /CC BY
Magnetic sound recording
This technology allowed us to record high-quality sound and worry less about possible mechanical damage to the media. Although by the look at her early implementations it is difficult to say that she was destined to reverse the idea of music. The father of magnetic recording is Danish engineer Valdemar Poulsen, who at the end of the 19th century received a patent for steel wire audio recording technology and developed a telegraph . But the device was not the most convenient to use and could not stand the competition with the more affordable phonographs .
Although the situation has changed since the beginning of World War II.
During the fighting, the wire carrier was used for audio recording in the field - it easily tolerated temperature changes and was not afraid of moisture. However, the playback quality left much to be desired. The problem was solved by German engineers by developing an iron oxide film and using the technology RF magnetization managed to improve the sound quality. They used film recorders to propagate that time.
Photo jglazer75 /CC BY/Ampex Model 300
Magnetic tape spread around the world after the war ended, when American soldiers removed confiscated equipment from Germany. One of them then developed a new playback device.
It saw the light in 1948 - it was the Ampex Model 200 reel. The system quickly became an integral part of the recording studios, where it was used for mastering. But the installation had a drawback - it was too cumbersome.
One of the first to solve this problem was solved by Polish audio engineer Stefan Kudelsky. In 1951, he independently developed and assembled a prototype tape recorder NAGRA I (KDPV depicts its improved version - Nagra IV-S).
It was portable, the size of a small suitcase. For its convenience, the system has been recognized among television, radio and film workers. NAGRA players used to climb Mount Everest and during space missions.
Soon the bobbin holders became the most widespread. More and more companies began to produce them, and these devices could be found in the homes of a large number of people - including in the Soviet Union. Who manufactured such devices in the USSR, we told earlier .
The magnetic recording technology was supposed to overshadow the unreliable records that were made from shellac .But the records were not going to lose ground and give way to the music market without a fight. In 1948, shellac was replaced by new materials - vinyl and polyvinyl chloride . They were more durable and less noisy during playback.
In addition to the material, the technology of applying sound tracks was improved - it allowed to reduce the speed of rotation of the plate without loss of sound quality. As a result, the volume of the drive increased - more music began to fit on it. 12-inch shellac plates held several minutes on one side, and the new vinyl could fit up to 23 minutes of audio.
This fact completely changed the approach to sound recording - before the records often contained only one song, now they began to post entire albums on them. But this topic is quite extensive and worthy of a separate material, so we will talk about the evolution of music next time.
Over time, not only the volume of the records has changed, but also the number of tracks. Until the 60s, records were released in monoform, but at the end of this decade appeared stereo records. In them, the left and right walls of the track were responsible for the respective playback channels.
By the mid-70s, the vast majority of vinyl releases came out in stereo - they played both in people's living rooms and on radio stations.
electrodynamic speakers . The first such devices were invented long before the war - they used electromagnetic capsule .
But their designs did not stand the test of time. Partly because such speakers had a high level of nonlinear and frequency distortion. To replace them came loudspeakers with a coil, a magnet and a diffuser - they began to be mass-produced in the 1950s. Less than ten years have passed since that moment when stereo equipment entered the stage.
One of the first appeared dual-channel tape recorders. They were followed by the production of commercial two-channel reels. In 1957, began developing stereo cartridges for vinyl players, and a year later the first to enter the music market commercial stereo album. We will talk about how new music developed in the next article.
Further reading on the subject in the Hi-Fi World:
How home audio developed - from song nights to first players
How Home Audio Has Been Available to a Broader Audience
Why did vinyl come back and how are streaming services related
Finds of an Audio Man: Where to Listen to the Music of Bygone Eras
History of Audio Technologies: Synthesizers and Samplers