Classical Guitar Study - Prototype Acoustic Frequency Response Test Records (1977-1978)

This document is a collection of internal acoustic frequency response measurement charts for various classical guitar prototypes, tested by technicians D. Johnson and J. Bud between December 1977 and May 1978. Each chart plots decibel output across the frequency spectrum (approximately 30 Hz to 9000 Hz) for individual guitar prototypes, with handwritten annotations marking resonance peaks and notable frequencies. The records appear to be engineering development documents used to evaluate and compare the sound characteristics of Ovation and Applause classical guitar prototypes, including one Takamine Classic C128 reference instrument.