Sound and LED Bending in a Retro Toy Enclosure

Circuit bending has a long and storied history, with tinkerers experimenting with the art for several decades now. Circuit bending is most often musical. Circuit benders take an existing consumer product, often toys with sound effects, and tweak the circuit to warp the sound output in response to some sort of input. Circuit bent instruments are usually used in experimental music or noise music, but you can occasionally hear them in more mainstream music. It’s rare for any two circuit-bent instruments to sound the same, because the sound is dependent on both the original device and the modifications. Lonesoulsurfer built his own LED & Sound Bending Machine from scratch and housed it within a retro toy enclosure.

The toy in this case was called “Road Race Game” and was more of an electromechanical novelty than a video game. It had no video output or digital logic of any kind. Instead, this Spy Hunter-esque game had a “screen” that showed a portion of the race track. That race track was actually just a continuously looping piece of paper printed with the graphics. An electric motor looped that paper and the player just moved an overlaid race car back and forth. It was an incredibly boring game that no kid today would enjoy, but Lonesoulsurfer thought the enclosure was very cool. So they completely stripped out all of the internal components and kept just the case for this project. With the stickers removed, the case has a neat retro appeal that is perfect for a circuit bending device.

Instead of circuit bending an existing electronic device, Lonesoulsurfer decided to build his own dedicated circuit from scratch. They designed a custom PCB for that circuit, which is built around an echo and reverb module. That also contains potentiometer knobs and momentary push buttons for bending the sound output in real time, two toggle switches, a battery, a buck converter, a charging module, and a small speaker. In addition to bending the sound output, this circuit also tweaks the output going to a plethora of LEDs. That means the LEDs are sound-reactive in a sense, though they’re really responding to the circuit bending itself and not directly to the sound output. Those electronic components were all housed within the toy enclosure with the controls mounted to the outside. With the addition of some control labels, the enclosure looks like it was designed specifically for this sound bending machine.