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I've read the posts on the different (and equally good) philosophies for back stiffness and tap tones (tune the back just above the main top frequency, or, way above). I'm wondering if one approach would be more favored if the back is a laminate (I usually use 1/8" Baltic birch). My instinct would be to make a laminate back pretty stiff, since it will have more damping and thus rob more power from the top. But then I see the lower end Taylors use no back bracing at all. Does anyone have experience with laminate backs, or any other insights?
Thanks, David

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David Malicky

I believe for classical guitars, Smallman laminates up very heavy backs. Schramm also builds some of his guitars this way. Schramm might chime in here.

Indeed the "Smallman" Lattice style guitar does have a very heavy, laminated back. However, it's a "horse of a different color"! those guitars are not at all like a standard classical guitar. They also have a very heavy plywood frame inside to increase internal rigidity and structure, so the top is the only thing producing much in the way of sound. Not true of other guitars.

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Waddy

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Sound Clips of most of my guitars

Thanks for the info! I think I'll stick to stiff for now, and maybe loosen it up after I understand the top better.

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David Malicky

In my lattice guitars I try to build them as close as I can to the Smallman design from the research that I have done. The backs are 6.5mm thick. I think that is close to 9 plys. I weight about 240 lbs and can stand on them with out any damage. I tested an old discarded back that was only 5mm thick by standing and bouncing and still no damage. Ideally what you want is thick, stiff and heavy. Light and stiff is not good. It would still move too much and absorb string energy.

The plywood frame isn't as heavy as it looks. One of the cool features of the plywood frame is the ability to change the size of the soundboard after the guitar is complete.