The Sweet, Joyful Tones: Exploring Tonewoods for Classical Guitars

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Traditionally, classical guitars are crafter with rosewood back and sides, spruce or cedar tops, necks of mahogany, and fingerboards of ebony.

It is the beginning of a complex story. Tonewoods come in various varieties and grades of quality. Their behavior as tonewoods also depends on how they are cut, dried, and aged.

Wood for the Top

In 1862, Antonio Torres (1817-1892) made a papier-mâché guitar. Torres proved this over a century ago by making a guitar with paper-mâché back and sides. The top is critical to the guitar’s sound. Spruce is the most widely used of the several “tonewoods” available.

There are several varieties of spruce used in building musical instruments. By far, the first choice for top-quality classical guitars is Alpine spruce (Picea abies), commonly called German spruce.

European spruce, which comes from thinning forests in Switzerland, Germany, and the former Yugoslavia, has, in recent years, become increasingly complex too.

Although Sitka or Englemann spruce from North America is inferior to European spruce for classical guitars, we construct steel-string guitars with these species because its slightly different fiber structure helps dampen the harsh harmonics of steel strings. Spruce grown in Hokkaido is a favorite of Japanese guitar makers.

In the 1960s, high-quality German spruce became increasingly expensive and difficult to obtain. Jose Ramirez III (1922-1995) began to explore the possibilities Western Red Cedar (thuya plicata) offered, commonly called Canadian Cedar or Canadian Red Cedar.

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Its close, straight grain, dimensional stability even under changing temperature and humidity, and tonal responsiveness made it an ideal substitute for spruce. Following Ramirez, famous luthiers such as Ignacio Fleta (1897-1977) and Daniel Friedrich (born 1932) began building guitars with cedar tops.

Barcelona became the hub of the guitar world in the early years of the 20th century—Segovia, Llobet, and Pujol were all there– and great luthiers like Enrique Garcia and Francisco Simplicio rivaled the Madrid school as heirs to Antonio de Torres. Following their lead came another great Catalan interpreter of the Torres-style guitar, Ignacio Fleta (1897-1977). Before switching to guitar-making in the 1930s, he was a violin and cello maker. By the late 1950s and into the 60s, Segovia played Fletas, followed by John Williams, the Romeros, and many others. - San Francisco Conservatory of Music.

Although some guitar makers can achieve good results with Cedar, others need help to make it work. The choice between spruce and Cedar is a matter of taste. Cedar guitars tend to be more responsive to low-frequency resonances. They are often sweeter and more mellow than spruce. Guitar makers know Cedar produces bright, clear guitars.

Overall, cedar guitars have a darker tonality, and the sound is less direct and more enveloping than spruce. The sound of a well-aged fine spruce top has an unmatched openness, clarity, directness, and edge like an arrow.

Medullary RaysPhoto byPinterest

Cedar tops, unlike those of spruce, do not improve with age. Cedar tops are responsive from the start. One can only play them in for a while to achieve the openness of aged spruce. A poor-sounding instrument will rarely become a good one with time. Spruce is subject to humidity changes more so than Cedar. This is why it is so vital that such woods be well-aged and adequately dried.

The older the spruce used by the maker, the better. Spruce is a hygroscopic wood; that is to say, it tends to absorb the same degree of humidity as the surrounding air, breathing moisture in and out with changes in humidity.

Wood cellulose is of two types: one that is amorphic and absorbs and returns humidity, and the other that is crystalline and does not absorb humidity.

Once the wood is cut and begins to dry out, returning the moisture it absorbed in its life to the air, the crystalline form begins to replace the amorphic form, reducing its tendency to absorb humidity and increasing its rigidity and capacity to vibrate with greater amplitude.

In short, as it slowly ages and dries, its tonal characteristics improve. While there are wood suppliers who guarantee the woods they provide have been aged 50 years, woods, once they reach their optimum dryness, will only improve if time passes.

Luthiers prefer air-drying to kiln-drying methods as it allows time for chemical changes to occur, which “cure” the wood. Wood may be seasoned in as little as three to five years when air-dried correctly. Luthiers, however, may cure their tops for much longer-- often twenty to thirty years.

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Three aspects of wood grain: straightness, density, and the welcome occurrence of medullary rays determine the quality of the sound produced by the top of the guitar. The straightness of grain is critical in determining sound quality and timber. The wood grain should be straight, with each grain parallel to the others. Since sound travels along these long fibers, any deviation from consecutive grains reduces strength.

One feature of delicate spruce tops is the presence of medullar rays, fibers that grow at right angles to the grain. While their natural function in the wood is to circulate starch and resin, they improve the tonal quality of the soundboard by providing links between the long fibers of the grain. Light medullar rays occur in Cedar but are not easy to see. Medullary rays in Cedar tops are not as important to sound as for spruce.

Medullary rays, also known as vascular drays or pith rays, are cellular structures in some wood species. They appear as radial planar structures perpendicular to the growth rings, which are visible to the naked eye. In a transverse section, they appear as radiating lines from the center of the log. To the untrained eye, medullary rays look like imperfections in the wood. The figurations of medullary rays form because the tree nourishes itself as it grows. A spruce top with many Medullary rays is quite a site and cherished by players.

Density is essential. The greater the density (number of grains per cm), the finer the top. Is the density uniform? Irregular spacing indicates that the wood has not been cut along the grain and is of an inferior grade. Generally, the distance between grains is less than 2 mm in premium-grade woods.

In recent years, some guitar factories have attempted to imitate the appearance of fine instruments by building instruments with laminated tops. Naturally, they sound like the plywood. Buyer beware. Make sure the instrument top is solid wood.

Woods for back and sides

Rosewood

Two types of rosewood create stunning tones in classical guitars and so-called flamenco negras: Brazilian rosewood (dalberia nigra) and Indian (dalbergia latifolia) rosewood.

Both woods are dense, resinous, and very handsome. Brazil has highly figured grain, and many consider it the most beautiful. Still, it is more brittle and difficult to work than Indian rosewood. By contrast, Indian rosewood tends to be straighter-grained and often contains purplish streaks.

Brazilian rosewood has become increasingly expensive and rare. In the mid-1960s, the Brazilian government, to divert more work to their sawmills, banned the export of logs. In 1992 dalberia nigra was declared an endangered rainforest tree and requires a CITES permit to export.

Indian rosewood, on the other hand, grows on plantations and so remains plentiful. Indian rosewood is dimensionally more stable and less affected by humidity and temperature changes than Brazilian rosewood.

Brazilian "dalbergia nigra"

Tonally, these woods have slightly different characteristics. Brazilian rosewood is less fibrous. It is hard and dense. Hence, it tends to reflect sound more, thus producing a bit brighter sound than Indian rosewood. This difference, however, can only be perceived by playing identically made instruments by the same maker.

There are significant differences in sound between makers using the same woods than between different woods by the same maker. A well-made Indian rosewood guitar may be infinitely better than an expensive Brazilian rosewood guitar by a luthier of lesser talent.

Other Rosewoods

Several species of Dalbergia (botanically true rosewoods) from Brazil find their way to the luthier’s bench as Brazilian rosewoods. Slab-cut, rosewood is similar in appearance and tonal character to Dalbergia nigra. They include Dalbergia martina (Madagascar rosewood) and Dalbergia retusa (Cocobolo). Woods in the Dalbergia family for guitar-making are:

• Dalgberia palo-escrito (Palo escrito).
• Dalbergia cearensis (kingwood).
• Dalbergia frutescens (Pau rosa, Jacaranda Rosa).

Hundreds of species are called “Brazilian,” such as Machaerium spp. (Caviuna or Fau Ferro). Because of this confusion and hype over Brazilian rosewood, we refer to true Dalbergia nigra as Brazilian rosewood. If we are unsure of the species, we call them figured rosewoods.

Laminated woods

Unlike the top, some fine makers have built guitars using laminated materials with excellent results. Jose Ramirez, for example, lines his traditional 1a Model rosewood guitars with cypress. He believes this lamination lends excellent stability to the back and sides, preventing warping and twisting and providing them with their distinctive dark sound. Henner Hagenlocher similarly lines the sides of his guitars with cypress.

Maple

Maple has been used in instrument making for centuries because its cross-grained structure allows planing to make light, thin, robust instruments.

Some modern luthiers, such as Paulino Bernabé, Pedro de Miguel, and J. A. Pantoja Martin, are again using maple to produce instruments with a sweet, joyful tone.

In the nineteenth century, luthiers chose maple to create fine classical and flamenco guitars. In fact, up to the 1930s, fine flamenco guitars continued to be made of maple, which, like cypress, can be planed very thin yet produces a somewhat fuller sound than cypress without being as mellow as rosewood.

Cypress

The use of thin, light cypress for the back and sides helps give flamenco guitars their vibrant and distinctive sound. This attractive blond wood is exceptionally light and can be worked much thinner than rosewood.

Choosing cypress over other woods has been a question of building affordable guitars. Few flamenco players could afford anything else, and cypress was abundant and cheap in Spain. In recent years, however, high-quality cypress has become increasingly difficult to obtain.

Coral

Coral is another wood that luthiers use to make flamenco guitars. This handsome, reddish wood-like cypress coral makes light, vibrant instruments. Harder than cypress, it produces very bright guitars. Pedro de Miguel and José Ruiz Pedregosa have used it to create outstanding flamenco guitars. Finding a Coral guitar in a retail store is not likely. A reputable dealer of fine classical guitars is your most dependable source of expertise and inventory.

Mahogany

Mahogany is one of the woods widely used to make affordable guitars. While it is much cheaper than rosewood, its tone is thinner and less resonant than rosewood. I say that mahogany plays an essential role in distinctive sounds. Twenty minutes with a Gibson J45 will convince you. Mahogany sits in the mix, and that is why so many musicians record with them.

Other woods

Makers have experimented with several other woods as alternatives to rosewood. Paulino Bernabé, for instance, has used pear wood in the bodies of high-quality classical and flamenco guitars. Paul Fisher has experimented with a Rosewood from Brazil wood, Santos Palisander, with good results. In their quest to find more affordable woods, guitar builders have also used sapele, an African wood in the mahogany family, sycamore from central Europe, American walnut, Koa wood from Hawaii, and Bubinga, a stunning reddish brown wood from Cameroon and Gabon.

Woods for the Neck

The wood for the neck must be strong and dimensionally stable, or it will warp or twist under the strings’ pull with temperature and humidity changes.

The wood also should be light to maintain the balance of the guitar. Because Honduran Cedar or Honduran mahogany is straight-grained when correctly seasoned and light and stable, they are the woods of choice for classical and flamenco guitar necks. Even so, to prevent warping, many makers reinforce the necks of their instruments with a bar of ebony running the length of the neck at a 90-degree angle to the grain.

Woods for the Fingerboard

The fingerboard requires a tough wood as the constant striking by fingers and rubbing of the strings will rapidly wear grooves in softer woods. Rosewood and Guinea Ebony are well suited for fingerboards. Although rosewood is more stable, ebony is a much harder wood. As a result, ebony finds its way onto fine guitars, where rosewood is the choice for entry-level instruments.

93 yr old Segovia practiced dailyPhoto byPinterest

Tonewoods in Action

Are you interested in hearing these masterfully made instruments played by world-class musicians? Spend some time with the following guitarists on YouTube.

• Andres Segovia
• Julian Bream
• Christopher Parkening
• Ana Vidović

Classical guitars provide hours of enjoyment for the guitarist and listener. It’s a wide world of music, and the classical guitar has a rich heritage, including some of the foremost artists and composers.

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Douglas Pilarski is an award-winning writer & journalist based on the West Coast. He writes about luxury goods, exotic cars, horology, tech, food, lifestyle, equestrian and rodeo, magazine features, and millionaire travel. 

 Share your thoughts and stories at dp1@sawyertms.com.