Noise-free distortion pedal for electric guitars : Designing and constructing a unique distortion pedal for live playing guitarists

Abstract: Guitarists using effect pedals to alter the way their guitar sounds often face the problem of loud noise when they want their guitars to be completely silent. This can be the result of using a distortion pedal which works well when you’re playing, but not when you have a brief pause. This project focuses on developing a complete prototype of a distortion pedal that has an adjustable mute circuit, also known as a noise gate, built into it. The project pedal consists of some functions which commercially available effect pedals have; 6.3 mm input jack, on and off switch, both a battery connector and a DC-jack, and adjustable knobs for the different effects like drive, tone and volume. The distortion circuit is inspired by the BOSS SD1 SUPER OVERDRIVE pedal and the muting function is constructed with Junction Field Effect Transistors.Two prototypes were constructed; one with hole mounted components, and one with surface mounted components. They both work largely as imagined. When the guitar is played, the desired distorted sound can be heard and adjusted with a drive, tone and volume control. When the guitar is not played, all unwanted noise is completely muted. A sensitivity adjusting knob allows for different signal strengths to be muted.The chosen method for muting the signal introduces a short and faint unwanted noise during the muting process. While it would have been better to eliminate this noise too, the prototype introduces something new and helpful for guitarists using distortion pedals. With more work, this way of integrating a mute circuit in distortion pedals could potentially set a new standard.