From Chrysler Press Release — for use October 12, 1955:
For 1956 Imperial introduces the high fidelity record player. Small, neat and compact, the unit measures only slightly more than four inches high and less than a foot wide. It is mounted under the instrument panel, and plays through the radio speaker.
Each side of the 7-inch records is good for between 45 minutes and a full hour of uninterrupted play. A choice of popular and classical recordings, as well as recorded readings, is available. A storage space at the bottom of the unit holds five records. These are held flat by light spring pressure which prevents them from warping.
The records are of true high fidelity quality and the frequency range of the record player reaches 10,000 cycles per second. The door of the player opens downward and the turntable chassis can then be pulled out for easy record changing. The records are centered over the spindle by stops at the rear of the turntable.
An elastic three-point suspension cushions the turntable against road shock, and is designed to pivot about a point on the arc swept by the stylus as it traverses the record. This reduces turntable motion to a minimum in the vicinity of the stylus.
The pickup arm, though conventional in appearance, moves only in a horizontal plane. Hence, there is no problem of the arm itself bouncing when the car travels a rough road. Only the stylus can move vertically, and this is spring-loaded to hold the point against the record with a pressure of two grams.
The pickup arm is also counterweighted, so that its center-of-mass is at the pivot point. This offsets the tendency of the arm to swing in response to fast acceleration, heavy braking and hard turning. In repeated tests of the record player, mounted in a car and driven over various kinds of road surfaces, it has proved extremely difficult to jar the arm off the record or even make the stylus jump a groove.
Read more at http://ookworld.com/hiwayhifi.html