Level of Education of Students Involved
Undergraduate
Faculty Sponsor
Pete Johnson, Andy Richter, Rob Swanson
College
College of Engineering (COE)
Discipline(s)
Mechanical Engineering, Physics
Presentation Type
Poster Presentation
Symposium Date
Spring 4-24-2025
Abstract
To better understand the effects bracing structures have on guitar sound quality, we are investigating how adding weight to an acoustic guitar's soundboard affects its resonant frequency. Based on the typical mass of a guitar soundboard (200 to 250 grams), we predict that even a few grams of additional weight will yield measurable differences in the frequency peaks. Our objective is then to determine the minimum mass required to produce noticeable changes. We measure resonant frequencies by striking the guitar bridge with an impact hammer and recording the resulting frequency by measuring the displacement of the soundboard with a capacitor probe. This approach has provided consistent and reliable data throughout the years this experiment has been performed. Our next experiments will build on this foundation, in which we will incrementally adhere weights directly to the soundboard, increasing the mass with each set of tests. Previous data suggests that the system is sensitive enough to detect subtle variations. We hypothesize that adding small masses suffices to alter the resonant frequency, but the challenge of determining the minimum mass required remains. By systematically altering the weight, we aim to identify the threshold where frequency changes become significant. Future experiments will expand on this work by exploring how different weight distributions and placement locations on the soundboard influence resonant frequency. These investigations will contribute to a deeper understanding of how physical modifications, such as the bracing design, affect acoustic performance.
Ruth Cook (Mechanical Engineering), Thane Martin (Mechanical Engineering), Chris Noga (Physics) Advisors: Pete Johnson, Andy Richter, Rob Swanson
Recommended Citation
Martin, Thane T.; Cook, Ruth; and Noga, Chris, "Guitar Research" (2025). Symposium on Undergraduate Research and Creative Expression (SOURCE). 1453.
https://scholar.valpo.edu/cus/1453
