The Art of the Creative Short Circuit

Jan 1, 2003 12:00 AM, By Qubais Reed Ghazala

           
 

A Beginner's Guide to Circuit Bending

Not that long ago, a short circuit in audio electronics was considered to be only one thing: destructive. But nowadays, an audio short can function as a constructive as well as a creative element.

The creative short circuit, or the technique that I call circuit bending, is a form of hardware hacking or modding, but with two important differences. First, whereas hackers usually know something about electronics, you don't need any real knowledge of electronics to circuit-bend. Second, while most people hack an instrument with a particular goal in mind—such as increased frequency range or cleaner outputs—the circuit bender works improvisationally and has no idea where the trail will lead.

In circuit bending, the instrument shapes itself by telling the bender what it can do. In this way, circuit bending has turned the electronic circuit into an immediate “canvas”; a circuit is accessible at that moment to everyone for the creative act. No theoretical knowledge is required, and on the first occurrence of experimentation a one-of-a-kind instrument is created.

SHORT YOUR OWN

Before I go into detail about how to build an Incantor, which is my design for bending a Speak & Spell, a Speak & Read, or a Speak & Math toy, I will begin with a general primer on circuit bending. Circuit-bent instruments can sound like just about anything, real or unreal. To hear what a typical Incantor sounds like, check out the audio examples online.

Circuit-bent instruments can retain their original voices, especially if the bender makes only modest adjustments in timbre or envelope. It is the deep end of circuit bending, however, that most people find enticing. Many circuit-bent instruments produce fascinating aleatoric music under the “clear illogic” of circuit bending. Here we seek to embrace, rather than tame, the chaos.

CAUTION BEFORE YOU BEND

Although circuit bending is simple, it is a try-at-your-own-risk endeavor. Never attempt the following procedures on anything that is plugged in to an electrical outlet—not even through a wall wart. You want no relationship whatsoever with the power mains, secondary coil or not. Transformers can fry and shunt, and wall-wart electronics are often shoddy. Circuit bending is only for battery-powered circuits of 6V or less.

FIG. 1: For body-contact circuit bending, hold the screwdrivers in your hands as you search for places to put contacts. In this photo, switches have already been connected to the circuit board.

Never bend a circuit that you'll miss if it fries. Bending is more for the abandoned circuit—like the sound toys that you see in thrift shops—than it is for your vintage stompbox from the '60s. Anyone can destroy a circuit in a moment with the wrong connection. But don't let that stop you; it's more likely the result will be unusual audio artifacts.

Soldering is an important aspect of circuit bending and is fairly easy to learn. For this article, I will assume that your soldering skills are such that you can make quick and precise connections. Quick, because some components can be damaged by the heat of excess soldering, especially since the bender may at times find it necessary to solder directly to integrated circuit (IC) pins leading to delicate electronics inside the IC. Precise, because, as in the example of IC pins, clearances can be minimal. The danger is that you may create an inadvertent “solder bridge” between IC pins (or other tightly spaced metals, such as printed circuit traces, component leads, and so on) that were not meant to be soldered.

Practice soldering until you feel comfortable, quick, and precise. In addition, practice safe soldering. Vent smoke away from you, wash your hands thoroughly after soldering to remove lead residues, and wear safety glasses.

If you're new to the field, I recommend that you read an electronics book geared toward beginners. Forrest M. Mims's books Getting Started in Electronics and the Forrest Mims Engineer's Note-book (both available at Radio Shack, among other places) are good to begin with. These guides explain useful terms and cover how various components7mdash;switches, potentiometers, resistors, capacitors, and LEDs—operate. The books also cover the basics of circuit construction and lead into more advanced subjects.