These unique turntables have been around for almost 20 years, and we know almost nothing about them. In 1930, at the peak of popularity of shellac gramophone records, German engineer Karl Daniel proposed using a new material for sound recording - polyvinyl chloride. Gramophone equipment manufacturers and record companies were lukewarm about the idea. (and we earn not so bad).
So the idea would have died out if Karl did not have his own radio factory "TEFI". It took almost 5 years to finalize the idea, and the release of a completely new sound carrier - vinyl tape in a cassette - began.
In fact, the same recording technology was used: a sound track in a spiral, a needle for playback. Only the audio track was cut on a flexible loopback tape and laid in a neat bay. The principle of laying the tape in an endless bay is better to watch on the video:
Karl Daniel manages to bypass gramophone records in terms of recording quality, duration (4 hours versus 5 minutes), size, but the recording market is still indifferent. Then Karl decides to promote the technology alone. His firm"Tefi" produces turntables and radios with cassette playback device "Tefiphon", and the sale goes through a network of company stores.
Small cassettes - 15 minutes, medium - 1 hour, large - 4 hours.
All the popular artists of those years had long-term contracts with record companies. Karl is left to release albums of little-known artists and classical music. Sales are going well until LPs hit 33.1 / 3rpm. in 1948.
The new standard has significantly improved the playback quality, and most importantly, the number of disc playbacks has increased without loss of quality. This was achieved by dramatically reducing the stylus pressure on the sound track. If in gramophones and Tephiphon the needle pressure reached up to 100 grams, then in LP records the needle pressure was only 1.5-5 grams. This is what a needle looks like on a vinyl record under a microscope (magnification 1000 times.)
the tip of the needle is blunt. With wear, the sidewalls are grinded, the needle becomes sharp and begins to destroy the sound track.
Soundtracks of different styles of music look different on the record
Trying to compensate for the falling demand for tephiphons, the company starts looking for foreign partners-dealers.
In the early 60s, Westrex began shipping cassettes and players to the United States through Western Electric. However, US sales were also very modest. In 1965, the production of Tefifon cassettes and players ceased.
The era passed, and with it the technology, but the idea continued to live and flourish, being reborn into the standard of tape cassettes. TRACK 8. The first tape cassette of this standard was introduced in 1964. Here's a comparison of TRACK 8 cassette and Tephiphon
The principle is absolutely the same, only the vinyl tape is replaced with a magnetic one. The TRACK 8 cassettes inherited from tefiphon and the main drawback is that they cannot be rewound, cannot withstand the load and the tape breaks. The maximum is fast playback.
The TRACK 8 audio cassette standard was very popular in America until 1982. Tape recorders for cassettes of this standard were produced by many companies in Japan and Europe. Even in the USSR, a tape recorder "Electronics ACC-1" was produced.
As for recording sound on tape, the Soviet engineer Alexander Fedorovich Shorin received a patent for a mechanical sound recording device back in 1927. As a tape, he suggested using a standard 35 mm celluloid film (there was no other in the USSR). With a tape length of 300 meters and more than 50 tracks, the total recording time was 8 hours. The Shorinofon devices were commercially produced in 1932. They both recorded and reproduced, therefore they were used as a reporter's voice recorder. Also "Shorinophones" were used when filming sound films.
For this invention, the engineer Shorin received the Stalin Prize of the First Degree.
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