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I have been pondering this question quite a lot lately. I realise that a lot of the build process factors into this (probably all come to think of it) but my question specifically relates to the initial thicknessing of the top plate. Some eg Kent Everett target the cross grain stiffness while most target along the grain stiffness as the bottom line when planning a build . I imagine there is an ideal ratio of lengthwise to crosswise stiffness most likely different for each body shape and size and also the intended use .ie fingerstyle ,bluegrass. Irrespective of how you ultimately tune the top, what method do you think will yield more consistent tone ?

Regards
Craig.

The ratio of cross grain to long grain stiffnes is inherent to the top and cannot be changed. So its best to pick one or the other and use it for your deflection measurements.

The luthier I learned from said that long grain stiffness has more control on the final tone of the guitar so that is what I measure.

The ratio of stiffness across the grain verses along the grain is inherent to the top but varies greatly from piece to piece. So that ratio can be used to determine what top to use for a given size guitar and/or desired tonal outcome. Mark Blanchard gave a seminar on this and I use this method as well.

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Randy Muth
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I use long-grain stiffness to determine how thick to make a top so that the deflection stays within reasonable limits. Long- to cross-grain stiffness ratio is, as has been said, more or less a property of a given top, and tells you more about what shape that top will work with than anything else. Mark Blanchard's talk on it at H'burg a few years ago is pretty much the best take I've seen. The bottom line from that is that if the top is floppy in the cross grain direction, it will probably work best on a narrow guitar, while the wider Jumbos and Dreads need higher cross grain stiffness.

I think that consistency of tone relates more to how well the top works within itself. This seems to be a matter of getting the top and bracing working together. There are a number of ways to do this. I use Chladni pattern testing, as does Mark Blanchard. Tap tones give much the same information, and Dave Hurd's deflection testing seems to work pretty well too. There's no one 'Right, True and Holy' way to do this, and lots of poeple get consistent results with all sorts of methods. I deeply suspect thatm in the end, we're all doing the same thing from different approaches.

Whatever you choose to do, I'm a big advocate of record keeping. At least then you know what you did, and how it worked, which is always a good place to start.

I`m with Todd on this one.No magic Voo-Doo for me.It`s all about the way the wood feels and the quality of the tap tone.
James

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James W Bolan
Nashville Tennessee

Thanks for your thoughts on this . I guess it comes back to building more instruments and keeping track of the details throughout each build. I'm always looking for shortcuts to world class tone but slowly coming to the realization that they don't really exist. John Mayes and Kent Everett make it look so easy flexing and tapping. And Al Carruth you do the same with the Chladni pattern testing. Thanks again for the reality check. At the end of the day building more instruments isn't all that bad really!:D

Regards

Craig

Put me in the "intuitive camp". I never could see reductionist theory in stringed wooden instruments, but to each their own. It just takes a few (or many) builds to "get it". I don't even keep track of numbers except in my head.
A lot of tapping, scratching, and scraping at almost every stage of each build, culminating in a whole lot of tapping, scratching and sanding and scraping when the box is together. Sometimes I use a Hacklinger to see where I am, but really don't write anything down. I've done it for 20 years with mandolins and it works for guitars too. It's a feel for the wood...

To me, the tone is in the wood and can't be changed.It can be brought out by design and voiceing to get more balance and power but not changed.

How the wood feels and the tap tone is precisely voodoo, imho. Keeping a detail record, doing Chladni, etc. is a reality check that takes out a lot of subjectivity. I follow both ways. I have a wonder pair of numbers for the lengthwise stiffness and weight of a top, and I also know what is a great stiffness/weight for a brace too, but that doesn't stops me from going lighter or stiffer when my intuition tells me to. In fact I break the number rules every time, gambling with what my intuition guessed about when to stop planing the top or carving the braces.
I started to write down everything from several reasons. I had no1 to teach me in real. Sure you can learn a zillion things if you filter the internet info correctly, but you will never learn how to feel the wood without actually... feeling it in real lots of times. So I started to write down densities, deflection, weight for every single bit that goes in the guitar. Plus that I have poor memory. I just didn't want to build randomly, at lucks will, for the next 10 years or so. I want to have something that could help me understand, or at least give me the impression I am understanding things. Of course it is easy to dismiss the "technical" approach when you already have 20 years of experience doing it in a different way. I believe following both ways is the best way, at least for me, at least until I have enough trust in my intuition to renounce the numbers.

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Mark, i think the same. The real magic and beauty is with the wood mostly. I think the luthier should be an engineer using this magic potential in the first place. I guess it is easy to envision ourselves as a Michelangelo extracting a masterpiece out every bulk of marble, but it is a forced parallel.

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