Innovations over Time

In-Car Speakers
As drive-ins were being built at a modest pace in the late 1930's and early 1940's, several innovations greatly improved the movie-going experience. The most significant of these was the in-car speaker. While there was an early version of the individual speaker, used in the late 30's, which was simply a stationary speaker mounted on a pole near the car, in 1941 RCA announced the availability of the in-car speaker, which was designed to be hung on the car window. It was not widely used, however, until after World War II in 1946. This new speaker became a necessity as many communities began instituting noise ordinances which restricted the level of sound that could be heard beyond the drive-in lot. Although there had been many other contraptions devised to deal with the sound issue, the in-car speaker served as the best solution and opened the door for the massive growth of the drive-in industry during the post-war years.

Cinema Radio
In the early 70's, just as AM sound was coming into practical use and an estimated 97% of cars had AM radios, Fred J. Schwartz started a company called Cinema Radio after experiencing what he felt was poor sound quality at a drive-in.  Although transmitting a radio signal normally required an FCC license, drive-in owners were given an exemption, as their systems were low-power and could not normally by heard beyond the drive-in lot. While the AM system required that a coax cable be buried under the ramps to transmit the signal, the new radio sound would be welcomed by the drive-in operators because they were growing tired of finding many of their speakers either damaged or stolen at the end of the night.  Eventually, FM sound became available, providing better quality, and remains in use to this day at most drive-ins.

Set-up and Construction
The quality of the presentation and overall construction of drive-ins varied widely. Some were elaborate first-class locations with plenty of amenities, such as the West Side Drive-In in Detroit, the first of which to installed a merry-go-round in 1943. Other locations however, were very low-budget affairs with little more than a primitive wooden screen and a modest projection booth utilizing 16mm projectors.

The success of drive-ins after WWII and during their heyday in the 50's caused a trend toward ever-larger and more elaborate sites, such as the Bel Air Drive-In in Detroit, built in 1950. This location featured space for 2200 cars, an elaborate concession stand, along with a full playground and a train ride for the kids.   Taking the drive-in experience far beyond that of everyday cinema watching, operators offered scads of extravagant amenities such as live music, dance floors, picnic areas, playgrounds, pony rides, shuffleboard courts, swimming pools, fishing ponds, amusement parks, boat rides, diaper rooms, and even trapeze artists.     Along with these activities, some drive-ins also provided portable in-car heaters to enable year-round viewing, along with all kinds of products and contraptions for keeping rain off windshields and for deterring insects from bothering viewers.

Vital to the success of drive-ins was the concession business, as food revenue increased steadily during the late 40s and 50s. While some operators experimented with talk-back speakers to take orders and deliver food to the car, others had mobile carts patrolling the lots selling snacks. Overtime, owners discovered that concessions could be sold at a high mark-up and that revenues did not have to be shared with film distributors. To this day, food revenue remains extremely important to exhibitors, especially with film rental rates going as high as 80% on opening weekends for some features. In order to promote the concessions, most locations used the now-famous drive-in intermission films, popularized by the Filmack Company, featuring dancing hot dogs and countdown clocks that were supposed to mesmerize the audience members, wet their pallets and open their wallets.