brief history of the stereo 8
cartridges & cases

Although commonly referred to as 8-Tracks today,
officially they were known as "Stereo 8".

The Stereo 8 Cartridge was created in 1964 by a consortium
led by Bill Lear of the Lear Jet Corporation.

RCA first introduced these in the Fall of 1965 with 175 titles.
The next year saw the release of the Monkees first LP
on this new Stereo 8 format.


Early Lear Jet cases were made from polyurethane resin with a thin layer
of styrene laminate for the external glossy surface.

Billboard July 1, 1967


Time is not kind to urethane as it tends to crumble and fall apart
onto the cartridge (or your hands) leaving a mess.


The bottom tray was clear plastic so when you flipped it over
to see the track listings you just saw the label on the cartridge itself.
This bottom tray wasn't very well secured and when you picked it up
the wrong way it would sometimes slide off.

So in January '67 RCA discontinued the clear plastic tray and created a
white plastic bottom that had the label directly on it. This allowed the case
to snap shut. "More Of The Monkees" was released this way
and their first LP was updated with this change.


By May of '67 with the release of Headquarters the cases became
slightly shorter and they stopped making them out of urethane;
using plastic for the upper shell to match the bottom.



Their first two releases were subsequently updated
in the latter part of '67 or '68.


Finally, with the release of "Head" in December 1968
RCA switched to the paperboard sleeves.

This "Headquarters" with a paperboard sleeve
came up for sale in 2018. However it is unknown
if the other hard shell cases were also updated
with this kind of slipcover.



The "Lear Jet Pak 8" cartridges had a distinctive design identified
by a 1 by 3 inch slightly curved indentation on the lower front of the cartridge;
the end you inserted into the player.

"Lear Jet Pak 8" was also stamped into the back case top.
These are sometimes called 'flat paks'.

Lear Jet Pak 8

The cartridge was updated in early '67
and the name changed to "Lear Jet Stereo 8".
Both "Headquarters" and the 'Pisces' LPs were issued with these.

Lear Jet Stereo 8


Comparison of the two cartridges


The Colgems circle logo made it's first appearance
with their third LP release "Headquarters".

Exactly when the previous cartridges were
updated is unknown; certainly it was sometime after HQ.


Then in 1968 with the 'Birds' release RCA stopped using the
Lear jet cartridges altogether and the name was removed.
I suspect someone created a better working internal design
that improved reliability and playback.

Notice the three lower holes are missing
on the back of the cartridge.


Warranty Cards &
Cartridge Care

December 1966
Printed on light green paper,
This one came with my "Headquarters" Stereo 8.
On the last page the date is printed at the bottom;

Here are a couple of others
that are the same except for:

Dated September 1966


Dated September 1967

In late 1968 with the switch to paperboard slipcovers,
RCA began printing this information directly on the sides of the sleeves.