Investigation of the Electromagnetic Properties of Electric Guitar

The goal of the project described in this thesis is to gain a deeper understanding of the detailed physics operative in electric guitar pickups in order to be able to build pickups with a more versatile set of tonal qualities. Using phase sensitive lock-in amplifier techniques, the complex impedance of several different guitar pickups was measured over the frequency range of human hearing. The impedance data was fit to a lumped 4-parameter circuit model of the electric guitar pickup. Extracting the frequency dependant parameters of this model (i.e., inductance, capacitance, and AC resistances) from the fit provided valuable insight into the electromagnetic properties of pickups. The methods outlined in this thesis have been successful in analyzing the circuit properties of a wide variety of different pickups, and should be instrumental in carrying out deeper investigations of the physics of pickups in the future. Introduction/Motivation Electric guitar pickups are crucial pieces of hardware, because they convert the vibrations of guitar strings into an electrical signal which is sent to an amplifier. The electromagnetic properties of pickups have a profound impact on the tonal qualities of an electric guitar. A deeper understanding the physics of electric guitar pickups is essential in order to obtain a better understanding of how to construct pickups with desirable tonal qualities.