For guitarists looking to add a unique stuttering effect to their playing, a Guitar Killswitch is a fantastic modification. The beauty of a killswitch lies in its simplicity, especially when it comes to the type of switch required. Essentially, you need a switch that can interrupt the signal from your guitar’s pickups, and for this, a basic on/off switch is perfect.
The most straightforward option is an STSP (single throw single pole) switch. These switches are characterized by their two terminals on the underside. When activated, an STSP switch simply connects these two terminals, completing the circuit and allowing your guitar signal to pass through. In its resting state, the terminals are disconnected, cutting off the signal – exactly what we need for a killswitch.
Alternatively, you could consider using an SPDT (single pole double throw) on/on switch. These are a little more versatile, featuring three terminals. An SPDT switch works by connecting the middle terminal to either one of the other two terminals depending on its position. For a killswitch application, you would only utilize two of these terminals – typically the middle and one outer terminal – effectively using it as an on/off switch, similar to an STSP.
Beyond the terminal configuration, switches are also categorized by their mechanical action: momentary or latching. Momentary switches only alter the circuit while you are physically manipulating them. As soon as you release the switch, it springs back to its original position. Think of a doorbell button – it’s only active when pressed. Latching switches, on the other hand, maintain their state after you toggle them. Like a light switch, they stay in the “on” or “off” position until you change them again. Pickup selector switches on guitars are a prime example of latching switches. For almost all killswitch applications, a momentary switch is preferred. The exception, as mentioned in the original article, is using your pickup selector as a killswitch, a technique popularized by guitarists like Tom Morello. However, if you’re considering adding a dedicated killswitch, you likely want a separate, momentary switch for that stutter effect.
Finally, within momentary switches, there are two further types relevant to killswitches: “always on” and “always off”. An “always-on” momentary switch is normally closed, meaning the circuit is complete and your guitar signal passes through continuously until you press the switch. Pressing the switch breaks the connection, creating silence. Conversely, an “always-off” momentary switch is normally open, meaning the circuit is broken, and no signal passes until you press the switch. Pressing this type of switch completes the circuit, allowing sound to pass only while pressed. The choice between “always-on” and “always-off” depends entirely on your desired killswitch behavior and how you want it to interact within your guitar’s circuitry. Consider whether you want the sound to be constantly on, interrupted by pressing the switch, or constantly off, activated only when the switch is pressed.
