Post production audio consoles are used to add the soundtracks to film and television shows. The dialog, special effects, and music all come from diverse recorded sources and are mixed to produce the final product. Note that there are four operator positions at the console. Disney uses a separate engineer to handle the dialog and effects and two to handle music. One guy on music is more common.
One problem that studios faced before console automation was how to handle multiple language releases. It was complicated and expensive to remix a movie from the ground up just to change the dialog. The PP-1 was the first automated console available to the industry. It was an analog console with its main functions such as signal level and routing digitally controlled, and it had a data base system that memorized operator inputs 30 times per second. With the effects and music under computer control, redubbing dialog is much simpler. 35 years later, this level of automation is commonly available on a Mac or PC.
I was one of the engineers who designed the PP-1. My main contributions were the 3-/5-channel plus surround panning circuits, the monitor system, the low-noise processor master clocking system (there are over 50 microprocessors running in sync), and the Autograph. The Autograph was a fully automated reverse engineering job of the industry-standard Cinema Engineering passive graphic equalizer.
Our team started working the initial design of the PP-1 in November, 1978. Serial Number 1 was delivered to Disney in May, 1979, and commissioned over the next couple of months. The first feature film to use it was The Black Hole.