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Still in the pursuit to demistify the process of getting a luthier guitar for a newbie at the Montreal Guitar Show... I would like to ask you what are the choice of woods (including specific benefits) for a classical guitar?

I know that many classical guitars purists, both players and builders, would never, ever, use Redwood for a soundboard. All the more reason why I did...

That depends entirely on what tradition you are building in.

For a snob like Segovia, only the most expensive Rosewood would do.  He desperately wanted to elevate the guitar to a higher social strata, and using expensive wood would suffice.  People have been debating the sonic properties ever since.

For Torres, he was quite happy using other woods.  The extant records show that he used maple nearly as often as rosewood.  Mind you, in his circumstances, our common maple was exotic.

The common, to Spain, use of Cyprus, made wonderfully sounding guitars.  Many, including Jose Romanillos, consider it a favourite regardless of public opinion.

The choice of Spruce or Cedar tops really has more to do with what sort of sound goal you have.  Both can give exceptional results.  Most builders working towards a traditional sound prefer European Spruce.  This is, after all, the wood that defined the traditional sound.

Then there's the whole kettle of fish as to other construction issues: are you interested in a very traditional "Spanish" sound? or something else.  Many builders and players like the results of Lattice bracing, which carries with it many other construction considerations.

There is far, far, more to a classical guitar than just wood choices, though that may at first be the most obvious.

So, there you go.  Simple, isn't it?

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and what was your impressions of its suitability as a top wood?
it's Boaz Elkayam's favorite top wood for a classical and the great late Paulino Bernabe did more than a few of them...

Given the quasi-religious overtones of the 'wood' discussion on so many lutherie 'boards, this one could get interesting.

;)

I fear I'm a structural-functionalist: I tend to look at woods for guitars in terms of my understanding of how they contribute to tone. Since it's harder, in my estimation, to make a good classical guitar than a good steel string, I tend to be more careful with wood selection on classicals.

The problems of classical guitars stem, in large part, from the nature of the strings. Nylon strings weigh less than steel, and carry less tension, so there is less energy available to drive the top. Nylon also has higher damping in itself, and loses more energy to air drag because of the larger diameter. This tends to cut down drastically on the energy in the high frequency range. The problems you run into making a good classical are in getting decent volume, and enough high end to give 'clarity' and 'carrying power' to the tone.

The easiest way to get more power is to make the top light. The limiting factor is the stiffness of the top; it needs to be thick enough, or well enough braced, to not fold up too soon. Thus, it seems to me, that the stiffness along the grain of the top wood is most important.

It turns out that long grain stiffness varies pretty closely with density: all of the 'usual suspect' top woods fall near the same line when you plot lengthwise Young's modulus against density. In these circumstances the less dense the wood is, the lighter the top is likely to turn out. So these days I tend to choose my top woods for classicals more or less according to density.

Low damping in a top wood can be a good thing as well, as it tends to minimize high frequency losses. However, it does tend to give a particular color to the tone: both Western Red Cedar and Redwood have notably low damping and similar tone. Redwood can be a fairly dense wood, but in many cases the low damping seems to make up for that.

For the back it seems as though the best wood would have fairly high density, and low damping. To the extent that the back is a 'reflector' the high density keeps it from vibrating too much, and low losses in the wood help to minimize the loss in high frequency energy. Low damping, in both the top and back woods, seems to contribute to 'color' as well.

As far as particular species go, I'm less fussy so long as they measure up. Cedar and Englemann spruce both tend to have low density, with Euro a little higher, but I've got Sitka and Red spruce tops that are in the same range. Redwood has other charms!

Dense, low damping woods like Brazilian rosewood work well for me, and there are 'local' substitutes like Osage Orange and Black Locust that also do well. Again, there's a lot of overlap, and a large number of woods that can be suitable.

Finally, I'll say that I consider the maker to be the more important factor. I once made a 'matched pair' of classicals, one from BRW and Euro, and the other from local White spruce and White Oak, and found the differences between them to be minor. They were both good guitars.    

[QUOTE=vachterm] and what was your impressions of its suitability as a top wood?
it's Boaz Elkayam's favorite top wood for a classical and the great late Paulino Bernabe did more than a few of them...[/QUOTE]

Sounds fine to me. It can be played quite loud. Have a listen: http://www.youtube.com/watch?v=UQCQYf_aW8g