In parallel with the development of the Compact Cassette, separate developments had been occurring in the USA, led by entrepreneurs Earl Muntz and Bill Lear, the latter of whom ran the airline Lear Jet. Whereas Muntz was primarily concerned with finding a way to easily playback jingles and adverts for radio (for which a version of his cartridge became the industry standard), Lear saw the potential to extend the format to the market for "music on the move".
This is how EMI's 8-Track Cartridges were presented upon their introduction in February 1968.
8-Track Cartridges differ from cassettes in that they use what is termed 'co-axial' spooling - the take-up and supply are on one and the same reel.
The tape is pulled out of the centre of the reel, wound around to the top of the cartridge where access holes allow contact by the playback head and capstan (through which the player's motor drives the tape forward). The tape that has pulled past the access holes is pulled back onto the outer side of the reel by the tension created by pulling on the inner side.
The simple mechanism that this enabled the players to use suited themselves to mobile applications where simplicity and cheap manufacture were the main aims, such as for aircraft and automobile music systems. They also found niche uses for 'mood music' (or 'Muzak') in supermarkets and in lifts. Even arcade games of the 1970s (especially the mechanically driven type, like duck shoots and mole bashers) tended to use 8-Track cartridges for sound effects, as it was easy to switch and mix background music with vocal 'stabs' and other effects like explosions, shots and congratulatory fanfares.
The 8 available tracks are used to provide 4 stereo 'programmes' - a bit like sides on a cassette. However, all the Left channels are stacked together on one half of the tape's width, and all the Right channels on the other. The narrow track width tends in many circumstances to cause leakage between adjacent tracks, meaning you get to hear faint 'bleed-through' of one programme onto another - very often noticable in the gaps between songs. However cartridges in good condition played on well-aligned machines don't suffer from this to a degree sufficient to cause annoyance. The ends of the tape loop are joined by a short piece of foil strip, which is used by the player to determine when to switch programmes.
On the underside of the cartridge can be seen the tracklisting, credits and corporate information such as label logos, catalogue numbers, etc.
In line with other record companies at the time, EMI elected to use a sticky label on the front of the cartridges themselves to provide the 'cover image'.
However on top of this, the cartridges were packaged in generic cardboard wrappers as seen here. These had a large rectangular cut-out area on the front to reveal the cover label.
The side panels carried a slogan devised just for the format: "BIGGEST SOUND AROUND". This slogan would survive into some of the future re-designs.
Finally, this whole ensemble would come shrink-wrapped for delivery to the stores.
The cover labels initially contained a first stab at a special logo for "8" Track Stereo Cartridge "Continuous Play Tapes" aswell as a large indication of the tape speed,
3 3/4 IPS (see above), but these features were soon dropped.
Note that the "8" logo and 3 3/4 IPS indications were quietly dropped from the top label, since there was no longer space for them. These cartridges would originally have come in the blue wrappers shown above. Most owners discarded these after opening, considering them simply to be part of the packaging you threw away.
Without the box, EMI's branding presence was left rather sparse on the cartridges themselves.
Sensing this, they decided to show clearer branding on the labels, as can be seen on the following page:
A different 8-Track Stereo Cartridge logo was used on the cardboard wrappers which, on their reverse, showed a rundown of some of the first releases to be made available on the format (left).
On early titles like the Mama Cass example shown above, the top and underside label were one continuous piece of paper, wrapped around. However this type of label soon gave way to two separate labels, most likely to allow for easier manufacture, as can be seen below.