The Kasha tradition
Kasha Classical Model
Michael Kasha (1920-2013) was an American physical chemist and molecular spectroscopist. He had great success in this career as a research scientist and professor at Florida State University, but he also took a keen interest in guitar acoustics and design. In the 1960’s he partnered with luthier Richard Schneider and set of on multi-decade project to radically change the design of the instrument to increase its power and tonal capabilities. They sought the assistance of Andres Segovia as an advisor, and ventured both into the steel string as well as the classical guitar genres. Over the years the design concepts were modified and refined. It is a complex design with many degrees of freedom for optimizing the sound.
Two key elements (there are many which could be discussed) of the Kasha concepts are radial tone bars and strong bracing asymmetry with a matching complementary bridge design. The Azaret version of the Kasha concept incorporates these and others while maintaining more traditional design approaches on other aspects of the instrument. The sound of the Kasha design can be characterized as lush and full. The nature of the soundboard bracing provides for a much greater number of vibrating modes which result in high overtone content in the notes as well as a more complex sound radiation field. The sound is often perceived as very warm and three dimensional.