abstract: Traditional consensus in duos with grand piano has been that issues of balance between piano and the other instrument can be corrected through lowering the lid on the piano, particularly when the other instrument has been thought of as less forceful. The perceived result of lowering the lid on the piano is to quiet the piano enough so as not to overwhelm the other instrument, though the physics of the piano and acoustics suggest that it is incorrect to expect this result. Due to the physics of the piano and natural laws such as the conservation of energy, as well as the intricacies of sound propagation, the author hypothesizes that lowering the lid on the piano does not have a significant effect on its sound output for the audience of a musical performance. Experimentation to determine empirically whether the lid has any significant effect on the piano's volume and tone for the audience seating area was undertaken, with equipment to objectively measure volume and tone quality produced by a mechanical set of arms that reproduces an F-major chord with consistent power. The chord was produced with a wooden frame that input consistent energy into the piano, with measurements taken from the audience seating area using a sound pressure level meter and recorded with a Zoom H4N digital recorder for analysis. The results suggested that lowering the lid has a small effect on sound pressure level, but not significant enough to overcome issues of overtone balance or individual pianists’ touch. / Dissertation/Thesis / Doctoral Dissertation Music 2017