Listen to the sweet sounds of a fine acoustic guitar or violin, and you know that youâre hearing the music of heaven. But–other than the artistry of a musician or the workmanship of a skilled luthier craftsman–what makes a stringed instrument âfineâ?
The answer is wood. The finest instruments are made from the finest wood, and the finest wood comes from old-growth forests.
The reason that old-growth wood is best is that trees that grew in forests untouched by man survived in dense growing conditions with the little light that reached the forest floor. Such trees grew slowly, and the rings of the wood harvested from old-growth forests are close together, a quality that gives the wood an unmistakable strength and resonance when it is caused to vibrate by an instrumentâs strings. Count the rings on the face of a fine guitar or violin and youâll see that the instrument may have begun its life hundreds of years ago as a sapling struggling to find the light.
Of course, every species of tree has its own characteristics, and these qualities provide different âcolorsâ to the sound of an instrument. Spruce is the most common wood used for the top of a guitar because it resonates well at all tones, but other woods, like mahogany, might be used for a warmer, âdarkerâ tone. Cedar produces a mellow tone, but it is soft and easily scratched or marred.
Harder woods, like maple or rosewood, resonate brightly and are best when strength is needed, such as in the construction of the neck or fingerboard. When weight is an issue, ash is often used.
However, most of the old-growth forests are gone, having been harvested for a multitude of purposes, including home building. Modern logging companies encourage trees to grow more quickly so they can be harvested earlier. While this might be fine for construction lumber, it spells disaster for the instrument makers.
As a result, many exotic woods have entered the field, including koa, padouk, cocobolo, and zebrawood. But they can be expensive to harvest and bring to market. And, of course, they also have their own qualities that alter the sound of the music produced.
A fascinating alternative, though expensive, is the recovery of old-growth timber that has lain at the bottom of lakes and seas ever since the unfortunate lumber schooner transporting them sank long ago. In such an environment, the water is cold and low in oxygen. Over time, anaerobic bacteria works at stripping away the sap and other impurities in the cells of the wood. As a result, the tight-grained wood is filled with microscopic chambers, which, once recovered, dried, and milled, leaves the fibers of the wood light, strong, and resonant.
Of course, the process of finding, recovering, drying, and milling sunken virgin-growth timber is lengthy and costly. A guitar top made from such centuries-old wood might be worth its weight in gold.
A final alternative that has recently revolutionized the instrument-manufacturing industry is the use of materials other than wood. Today, it is possible to find fine instruments that are made primarily of synthetic materials, such as plastic.
One company that has pioneered the use of synthetic guitars is Ovation, which has manufactured such instruments since the mid-1960âs.
The idea came from Charles H. Kaman, an aeronautical engineer who was a pioneer in helicopter and aerospace design.
During the early days of helicopter development, the challenge was to find materials that wouldnât vibrate the aircraft to pieces as it flew. Over time, Kaman studied hundreds of compounds until he came up with a low-resonance plastic material that would hold together under the intense vibration of a helicopter flight.
Along the way, he discovered several compounds that did exactly the opposite–plastics that vibrated and resonated far too intensely for use in aircraft construction. But Kaman was brilliant enough to realize that the very quality that would cause hell for a helicopter pilot would be heaven for a guitarist.
After experimenting with the ideal shape to enhance the vibrations, Kaman came up with the Ovation guitar, a round-backed instrument that is essentially a synthetic parabolic bowl with a wood top. The bowl is made of Lyrachord, a material that interweaves layers of glass filament and bonding resin, which is then tuned at the molecular level to resonate musically.
The result is an instrument with strong projection that is able to âring,â or sustain a note, for a greater length of time than can be achieved from most woods.
Today, other manufacturers have taken Kamanâs work even further, and now it is possible to buy a fully synthetic guitar, a fine instrument that never set foot in a forestâunless, that is, you brought it along on your camping trip where the only wood nearby was burning in the fire.
