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Eight Track

Eight Track Tape Features?

Why were 8 tracks bigger than Cassette Tape and how did the mechanism differ from each other?

The first tape recorders were called "reel to reel". You had a reel of tape, you would thread this past the tape heads, and attach it to a Takeup Reel. You could play the tape, then rewind it. When they went to stereo, they built tape heads with two parallel music tracks, to allow for both channels. And most of these allowed you to flip the tape over and record the other way.. adding two more tracks in the other direction. So in essence, this was a 4-track design. Most of the 4-track decks when I got into recording (the 1970s) used 1/4" wide tape. More expensive professional tape decks used wider tape widths, to allow for more tracks and/or better quality.

http://en.wikipedia.org/wiki/Reel-to-reel_audio_tape_recording

A cassette (properly called a Compact Cassette, introduced in 1963) is essentially a pair of small reels, with the tape permanently attached and housed in a protective shell. This was much more consumer friendly, but retained much of the same characteristics of reel to reel, including Tape Reels that mounted on two moving hubs. They did some compromises here, though. They changed to 0.15" tape, to keep it small, and they ran the tape at 1-7/8 inches per second.. most Open Reel decks could go to 7-1/2 inches per second. Tape speed was a bit like MP3 bitrate... the bigger the number, the better the quality.

http://en.wikipedia.org/wiki/Cassette_tape

The 8-track (officially called "Stereo 8") came out in 1965 as a very different kind of tape. It was based on a continuous-loop tape... there's only one reel.. the tape loops form the outside of this reel around to the inside, and as a result, it can play forever, never needs rewinding or flipping over. To store more information on the same tape, they put in four stereo tracks, all going in the same direction. A bit of metal foil at the splice point (as a continuous loop, there had to be a splice) was detected and used to move the stereo pickup heads to the next of four playback positions.

8 track used the normal 1/4" tape, but with 8-tracks, it wasn't an obvious improvement over cassette. They also used a 3.75 inch per second playback rate, which did help on sound.

But one of the cool things about the 8-track was also its downfall. Unlike the driven reels in the cassette, the 8-track's single reel moved freely, just pulled along by the tape. No mechanical reel made it easy to design a tape that just popped into a player and out, no need for the player to be told to unload. Movement of the tape was achieved by rollers at the opening end. 8-track could sound better than cassette, in the early days. But due to is design (both the cartridge and the need to mechanically shift recording heads), players were easily knocked out of alignment, lowering the quality. Meanwhile, all kinds of technology got applied to the cassette, as it was quickly becoming the standard for portable field recording. 8-tracks made poor recording units, due to the endless loop and the jumping between tracks.

The relative huge size of the 8-track was probably due to the length of tape needed.. the slower cassette could use shorter tapes. Also, the back of the 8-track tape medium had to have a slippery coating, to keep the continuous loop mechanism functional.

http://en.wikipedia.org/wiki/Stereo_8

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Engineering group Downer EDI Ltd says the first Waratah train carriages are on track to be ready by the end of December, despite claims there could be a delay to the roll-out.The NSW government on Wednesday ...

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