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..... Trouble with that build was it had asymmetrical (traditionaly lower legs) bracing which made closing the ring on chladni tests a real bear.


Dave

Imagine a line joining the points where the lower X-brace arms intersect the edge of the top. Any bracing below that line will tend to open the ring+ near the finger braces. If the bracing is to the right of center, the ring+ will open on the left side. With a typical Martin style bracing pattern, the lower ends of both tone bars extend below the line on the bass side and usually cause the ring+ to open on the treble side. The lower brace is especially influential. If you taper the lower end of that brace off, the ring+ will close a lot easier. Leaving a scallop peak on the lower end of the lower brace will cause serious problems with the ring+.

On my guitars, I solved all this by running the tone bars horizontally, straight across the grain. One is behind the bridge plate and the other connects the lower ends of the X braces. Yes, my bracing looks a lot like the Larrivee pattern.

The double X has the potential to open the ring+ on both sides unless you you taper off the lower ends of the braces significantly. Otherwise I think it is a good pattern. Al Carruth has built some great sounding guitars with it.

Mark