Comparison Now, let's apply this to the sound difference between wooden guitars and graphite guitars. Wood absorption is non-linear throughout the audible spectrum, and therefore exhibits a very complex structure of missing, enhanced and mixed overtones. This means that a guitar soundboard made of graphite behaves in a nearly linear manner, displaying almost the regular overtone pattern of college physics. Thus a RainSong's damping is almost constant across the acoustic spectrum, rather than increasing rapidly at high frequencies. Since the higher frequencies aren't damped as heavily as in a wooden guitar, the trebles are louder.
High overtones are only slightly damped, and therefore display very little non-linear interaction.
The overtone sequence is pure, with few mix tones or missing harmonics. It is a proprietary process uniquely suited to RainSong's all-graphite construction, and patents covering it are pending. Until they issue I can't discuss the technique, but I can describe the basic acoustic physics of what we were trying to do and why we have succeeded. Basically, we wanted to increase the acoustic volume of our guitars. Since guitar soundboards, like airplane wings and speaker cones, should ideally have zero weight and infinite stiffness, we reduced the weight of the soundboard while increasing its overall stiffness and response.