Magic City and its add-a-ball twin, Magic Town, are a beautiful electromechanical pinball machines from 1967 designed by Norm Clark featuring artwork by George Molentin. The backglass depicts a bustling metropolitan scene with an elaborate fountain as the artistic focal point. The fountain is apparently a rendering of Buckingham Fountain in Chicago's Grant Park.
But as beautiful as it is, the game is missing something. "Designer Norman Clark tried incorporating a rotating color wheel in the backbox behind the fountain for a bubbling three-dimensional effect, but the feature proved too expensive and was never included in the game." 1 So instead the game has a few simple blinking incandescent bulbs behind the fountain.
Retrofitting a color wheel into the backbox as the designer intended would be very difficult. There is less than an inch of space between the backglass and the wooden panel that holds all of the circuitry in the backbox (relays, score reels, steppers, credit unit, etc.). Not only would room need to be found for a color wheel and its motor, a hole would need to be cut into the panel to allow the light from a bright bulb to fan out far enough to cover the entire fountain which is nearly 10" tall.
With the advent of LEDs, some collectors replaced the blinking incandescent bulbs with color changing LEDs with the same bayonet base used by the original #455 bulbs. While this mod certainly makes the fountain more colorful, the effect is more of randomly changing colors than that of a color wheel.
A recent mention of the omitted color wheel on an online forum got me thinking. The illusion of a color wheel shouldn't be hard to recreate with some addressable RGB LEDs and a microcontroller. So I ordered up a string of 60 LEDs and started working through the design.
I ended up with an array of LEDs mounted to the backbox panel just behind the fountain. Each LED can project a unique color and, with a little software, can be made to look like the colors from a color wheel.
On the left is the illuminated LED array and on the right is what it looks like when illuminating the backglass. The videos below give a better idea of what it looks like when the colors are in motion. The first video shows the initial prototype design while the second video shows the final design results.
This little project was built as a proof of concept to determine how well it might work and what the issues might be. I may consider making more if there's enough interest. If you might be interested in one for your Magic City or Magic Town use the Subscribe page to receive updates by email.