Mark does use Chaldni modes to tune his backs as he adjusts and braces the plates. The same principals apply to both the top and the back, it is just somewhat easier to visualize what is going on with a ladder braced back. Mark uses target Chladni modes to determine the Brazilian Rosewood back thickness and to guide him through the carving of the Spruce braces.
The modes are determined by the stiffness of the back plate itself (sans-bracing). Given the cross stiffness nature of Spruce ladder braces, they don’t really affect long-grain stiffness much at all. Mark believes that it important to get the target long-grain back stiffness by manipulating the Brazilian Rosewood plate thickness. The cross-grain stiffness Chladni modes can then be adjusted by adjusting the stiffness of the ladder braces.
Quote:
Originally Posted by mhw48
I am fascinated by the patterns of the Chladni modes on the top. I have to confess that I don't know very much about the thought behind the whole process. Does Mark also test the Chladni modes of the back of the guitar? I seem to remember reading somewhere that one of the ideas behind this particular method was to have the top and back exhibit the same patterns so that they were sonically working together -- but it may have been an article about violins rather than guitars.
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