Ovation Guitar #72 Internal R&D Description and Measurement Log

This is an internal Ovation research and development document tracking the construction, measurement, and acoustic testing of guitar serial number 0072, model 1687-7/1687-8, spanning from December 1976 through July 1977. The document records detailed physical measurements of string deflection (RL, SN, K, FF columns), brace weights, and modifications made to improve sound quality including filing braces and adding carbon reinforcement. The final page includes a frequency response graph taken by technician D. Johnson on 7-11-77, showing the acoustic output spectrum of the instrument from approximately 30 Hz to 9000 Hz.