A WOOD’S “TONE” DIFFERS DEPENDING WHERE IT IS USED
We refer to almost any wood used in the construction of a guitar as being “tonewood”, but any wood’s actual impact on your overall sound varies greatly depending on where it is used. Acoustic guitars are often defined by the wood used to construct their back and sides—a “mahogany guitar” or a “rosewood guitar”, for example—but the wood used for the top (soundboard) has the greatest impact on any guitar’s sound, followed by the back and sides, and then the neck and fretboard, arguably in that order (though opinions do differ). For top, back, and sides, solid woods are almost universally preferred to laminated woods.
TOP WOODS ARE KING
The core of what you hear in any acoustic guitar’s sound is generated by its top, or “soundboard”, so this wood is key. Spruce is the most popular variety: it is light, strong, and rigid, and has a sweet, round tone with appealing depth and good clarity. Cedar, popular in classical guitars, is also used in many flat-top designs, and provides a more “broken in” sound with a little more warmth and richness right out of the box. Mahogany, which is punchy with a pronounced midrange, is also occasionally used, as are some more exotic alternatives. Of course different varieties of each of these, from different geographical sources, will also vary in tone compared one to the other.
BACK AND SIDES ADD SEASONING
The wood comprising the back and sides of any guitar will couch the voice presented by its top, and season it accordingly. Rosewood, long considered an upgraded body wood, is known for its great balance and desirable blend of warmth, depth, and clarity. Mahogany also enhances a guitar’s warmth somewhat, but with a little more midrange emphasis and enhanced crispness. Maple, used in some big flat-tops like Gibson’s SJ-200, adds tightness, definition, and projection. As with top woods, different varieties of woods will vary too, and exotic alternatives such as koa, cocobolo, pau ferro, and sapele have their own voices.
NECK AND FRETBOARD FOR SPICE
Neck and fretboard woods also have some influence on a guitar’s overall tone, though less so than the top, back, and sides. Mahogany, far and away the most popular, is considered round, warm, and even, with good clarity. A rosewood fretboard adds a hair of depth and warmth to this impression, while an ebony ’board leans toward brightness and “snap”. As on an electric guitar, a maple neck—a lesser-seen ingredient on an acoustic flat-top, but occasionally used—further increases treble and clarity.
TONEWOODS MATTER, BUT CONSTRUCTION MATTERS TOO
As hung up as some players get on the ins and outs of tonewoods, it’s important to remember that a skilled luthier can make almost anywood sound good. Constructional factors such as top-bracing methods and bridge designs can have an enormous affect on how even that cornerstone ingredient—a guitar’s top—comes out sounding. Bob Taylor’s Palette guitars, with bodies made from palettegrade oak, have proved this point admirably, as has a guitar made by Robert Benedetto (though an archtop acoustic) out of knotty pine.