Wood is Wood - Until it is More

Western RedCedar

“The art and craft of Lutherie is not so much about exerting my will over the will of the wood but, rather, coupling alongside the wood and redirecting it’s path. Lutherie is more Aikido than Tae Kwan Do, more of a dance than a fight.” —Christopher Cozad

The right pieces of wood, worked the right way by the right person can become more than simply the sum of the parts. The wood seems to open up, blossoming and blooming, revealing itself in a most intimate interaction between man and nature. The end result of good design and expertise reveals an unprecedented physical, visual and auditory experience that can leave one at a loss for words.

The Sounds of Wood
The Sounds of Wood

Tonewood

The acoustic guitar is capable of producing musical sound primarily as a result of the kinetic energy of its vibrating strings setting the front plate (soundboard or top) in motion. The relationship between the front and the back of the guitar can be understood as an interaction between two plates. If one was to liken the soundboard to a speaker cone in a cabinet, it would be necessary to set the back of the cabinet in motion to complete the analogy. Another way to describe the relationship of the two plates is to consider the workings of a bellows, with air moving between the front and the back plates. Unlike a bellows, though, the plates of the acoustic guitar are rigidly held apart by the sides (ribs, rims) of the guitar. All three components (the front plate, the back plate and the sides) together form the body of the guitar which is, in effect, a soundbox or chamber. Air is moved in and out of the chamber through the soundhole (or port), via a pumping action that occurs as a result of micro-vibrations across the front and back plates. The woods used to construct the body chamber are often referred to as tonewoods.

Traditionally, acoustic guitar bodies have been built using softwoods such as Spruce or Cedar for the front plates, and hardwoods such as Rosewood, Mahogany, and/or Maple for the back plates and sides. Over the years, adventurous luthiers have explored the depths of wood resources and combinations. Today it is not unusual to see guitar bodies made using all hardwoods such as Koa, Mahogany, Myrtle or even all softwoods such as Douglas Fir.

This luthier believes that traits and characteristics of various species of wood are observable, if not recognizable. In order to offer a comparison between available species, I have compiled various measurements along my own general understandings and presented them on my Tonewoods page.

Tonewoods

This is, by no means, an exhaustive tonewoods database. I have simply included several of my favorite acoustic guitar construction woods, predominantly North American species found predominantly in the Pacific Northwest.

By strict definition, only a few woods are capable of independently producing what we would generally consider to be musical tone. Those that can are often said to have a vitreous or glass-like quality where, when struck, the sound they generate is likened to the ringing of a bell or gong. One outstanding example of such a tonewood is Brazilian Rosewood, traditionally used to construct the marimba, a percussion instrument made up of wooden bars that are struck with a mallet. Metal pipes suspended below the bars amplify the resonant frequencies. The size of the piece of wood alone determines the pitch of the note. Wider, longer bars of Rosewood reproduce lower notes, while narrower, shorter bars are responsible for higher notes.

Not surprisingly, the most common woods used in guitar construction, the Rosewoods, Cedars, Redwood, Spruces, etc. also happen to be considered true tonewoods.

Another understanding of the term tonewood applies to any wood used in the construction of a guitar. The overall sound of a given instrument is generally acknowledged to be the sum of its parts. Curiously, unlike a wood that rings like a bell when struck, a wood that simply goes thud! or thunk! may be incorporated into an instrument that sounds surprisingly good when played. (NOTE: This understanding lends credence to the belief that the design and construction of the guitar may play an even more significant role in the resultant musicality of the finished instrument than does the particular selection of the wood(s). See my article Handcrafted vs Factory-built for more on this topic.)

The cellular structure of a given wood determines its distinctiveness, both visually and tonally. Much like wine produced from grapes, guitars built from various species of wood can have definable characteristics. Just as a fine Pinot Noir wine is recognizably different from a Cabernet Sauvignon regardless of how it is produced so, typically, is Brazilian Rosewood recognizably different from Claro Walnut, regardless of how the guitar is constructed. However, two vintners may produce two distinguishable wines using the very same grape by altering their harvesting or fermenting technique(s). In the same way, two luthiers can produce two distinct guitars using the same wood, but altering their build methods. Debating the degree to which the senses can be trained to identify subtle variations in wine or food, let alone wood, is not the objective of this article, nor does this luthier believe it necessary to score perfectly in some blind Tonewood Identification Listening Test (B-TILT™ 😊) in order to appreciate one wood over another.

The characteristics associated with various wood species should not be confused with wood quality, nor should these characteristics be relied upon solely to determine the sonic potential of a given guitar. I believe that, in the right hands, measurable factors such as volume, mass, density, and modulus of elasticity (a given wood’s resistance to being deformed when force is applied) play the more significant roles in the overall tone and responsiveness of an acoustic guitar, and should be the determining factors when selecting wood. But that is a topic for another article.

The Pan Flute

While listening to David Döring perform Rolf Lovland’s You Raise Me Up on the pan flute, I paused to reflect on the contribution and role wood plays in my life. If you haven’t heard this before, I encourage you to have a listen (close your eyes and prepare for emotion):



David Döring

The science behind the pan flute makes for a fascinating study and is well beyond the scope of these simple paragraphs. I happen to think of the pan flute as the grandfather of the harmonica, comprised of several bamboo or cane tubes, each being closed on one end. Air is blown across the open ends and the fixed registers (controlled primarily by the length of the tube and fine-tuned using wax, cork, corn kernels or even small pebbles) can be increased dynamically by the amount of air blown. In the hands (or lips) of a skilled flautist there isn't much the simple, wooden pan flute cannot do.

The Marimba

In the video, below, Ivan Trevino and Michael Burritt perform Ivan’s marimba duo Catching Shadows. The traditional marimba is a percussion instrument made up of wooden bars that are struck with a mallet. Metal pipes suspended below the bars amplify the resonant frequencies. Much as the different lengths of wooden tubes used to construct the pan flute determine the pitch, the size of the pieces of wood used to construct the marimba also determine the pitch of the note. Wider, longer bars of wood reproduce lower notes, while narrower, shorter bars are responsible for higher notes. As you listen, focus on the fact that the sound is coming from the wood!



Ivan Trevino and Michael Burritt

Lutherie

I believe wood is intrinsically musical and the art and craft known as lutherie is all about coaxing that musicality out of the wood. As critical a role as design and construction play in the building of an acoustic guitar, there remains an understanding for this luthier regarding the working of the wood: It is not so much about exerting my will over the will of the wood but, rather, coupling alongside the wood and redirecting it’s path. Lutherie is more Aikido than Tae Kwan Do, more of a dance than a fight.

Identifying and respecting the individual traits and characteristics of each piece of wood is as much a part of the science of lutherie as are the specifics of construction. That science, consisting of all that has been learned through exploration and experimentation, provides a basis or foundation upon which to build one’s skills. It would be foolish to ignore the body of work amassed by those who have devoted their lives to the construction of the acoustic guitar. It would be just as foolish to assume all that ever could be explored has already been explored, and resign oneself to doing everything the way it has always been done. Because...

Wood is wood...until it is more.