Ovation Adamas 1687-7 Guitar #0051 Internal R&D Test Document

This is an internal Ovation research and development document from 1976 detailing the construction specifications and acoustic testing of an Adamas model 1687-7 guitar with serial number 0051. The first page records physical measurements including top thickness, brace weights, rim dimensions, and resonance levels (RL/SN/K) taken at multiple dates between July and November 1976. The second page shows a frequency response spectrum analysis chart conducted by technician D. Johnson on 11-30-76, with annotated resonance peaks and a handwritten note that 'overall amplitude is probably too low by 2½ dBa'.