The wire recorder had been developing for several years when in mid-40's, several companies began to work on a magnetic tape recorder. Several types of tape were introduced, including a plastic-based tape with oxide, which became the industry standard. Many professional tape recorders were introduced in the late 40's, and in 1950, two-channel tape recorders were introduced to make stereo recordings of music (for demonstration purposes).
"The first prerecorded tape format offered to the consumer was reel-to-reel, available as early as the 1950's. Its physical characteristics went through a number of permutations before standardizing; in fact, stereo reel-to-reel tapes were marketed before the introduction of the stereo LP. However, the material available did not include rock for some time. Aimed at audio enthusiasts who owned reel-to-reel tapedecks, the selections offered on reel-to-reel reflected the supposed partisan palates owners of high-end equipment were presumed to have, and the tapes were, for the most part, sold in hi-fi shops and electronic stores, not in record stores. Titles by rock artists did not take their place alongside the classical music, opera, ballet, and jazz offered on reel-to-reel until the mid '60s, after the successful marketing of pop and rock music on 4-track and 8-track cartridges...
"By the mid-60s, however, the marketers of prerecorded reel-to-reel tape, perceiving that the success of 4- and 8-track cartridges signaled public acceptance of tape as an alternative to vinyl, began to offer mid-brow titles alongside the classical, jazz and other styles which had previously been the extent of reel-to-reel's domain.
"Increasingly, only the best selling LPs were chosen for release on the format, which, although enjoying some popularity with audiophiles for a while, never achieved sales numbers of 8-tracks or (later) cassettes. The reel-to-reel format, like the other prerecorded tape recorders (unlike the hardware associated with the other casualties of the format war) remain for sale on the market to this day. Reel-to-reel's demise can probably be largely attributed to the fact that its mediocre production standards did not allow it to deliver on its promise of superior sound quality, disappointing the audiophiles who would perhaps otherwise supported the format. Prerecorded reel-to-reel tapes were available into the early 1980's, bolstered (as were 8-tracks) by being one of the options offered by the major U.S. record clubs."
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