» The Anatomy of an handcrafted acoustic guitar
» Tonewoods: sonic signatures.
» What is the benefit of a Handcrafted Acoustic-Electric
» Acoustic guitar body styles explained.
» Why are some handcrafted acoustic guitars more expensive?
» What to Look For... Handcrafted Acoustic Guitar.
The Anatomy of a Handcrafted Acoustic Guitar
Tonewoods: sonic signatures
There are a number of factors that determine the tonal properties of wood. In addition, tonewoods respond differently in the hands of different makers. They can also take on different characteristics when used in different models of guitars - even those built by the same maker. Whether a particular wood sounds good or bad ultimately depends on who is doing the listening, so any attempt to sort out distinctions can only be subjective.
Perhaps the most important factor a luthier must take into account is velocity of sound, which refers to the speed at which a material transmits received energy. A luthier must design with materials that facilitate the transmission of vibrational energy. Lively materials, those with a high velocity of sound, or low internal damping make the best facilitators.
Most luthiers believe that the wood chosen for the top is the single most important factor in determining the quality of tone of the instrument. It is also interesting to note that the wood itself takes on different characteristics depending on which part of the guitar it's used for. Makers of electric guitars with bolt-on necks have long been aware of the fact that neck and fretboard materials can have a significant bearing on tone. Bridge materials, like fretboards, cannot make or break an instrument, but they serve to enhance or constrain the tonal effects of other woods in the guitar's construction.
It's important to remember that wood species can be responsible only for certain aspects of the tone of any guitar. Equally important are design, skill of the maker, and the quality of each individual piece of wood used. Tonewood selection however, can be a determining factor in the creation of a very special guitar or a guitar designed for a specific purpose.
When used as a top, mahogany has a relatively low velocity of sound (compared to other top woods), considerable density and a low overtone content producing a solid tone, and responds best at the upper end of the dynamic range. Mahogany-topped guitars have a strong "punchy" tone that is well suited to country blues playing.
When considered for back and sides, mahogany has relatively high velocity of sound, which contributes much overtone coloration. While rosewood guitars may be thought of has having a metallic sound, mahogany guitars sound more wood-like. The harder, denser examples of these woods can take also on the characteristics of the rosewoods. Mahogany back and sides tends to emphasize the bass and the treble.
Mahogany necks help to create a warmer, more "woody" tonal range. The same holds true when mahogany is used as bridge material.
Koa has been used for soundboards since the1920s. This hardwood has a relatively low velocity of sound, considerable density and a low overtone content. Therefore, it tends to produce a solid tone that responds best at the upper end of the dynamic range. Koa has a somewhat more "midrangey" tone that works well for playing rhythm and truly shines in guitars made for Hawaiian-style slide playing.
For back and sides, Koa tends to behave much like mahogany in terms of adding tonal coloration, but its emphasis is again more in the midrange.
All the rosewoods contribute to tonal coloration. Brazilian rosewood is known for its high sound velocity and broad range of overtones, and is also characterized by strength and complexity in the bottom end and an overall darkness of tone in the rest of the range. Strong mids and highs also contribute a richness of tone to the upper registers. Rosewood guitars also have a pronounced reverberant-like tone quality, caused by audible delays in the onset of certain harmonics. Brazilian rosewood has tremendous clarity in the bottom end and sparkle in the top.
When used for necks, Brazilian rosewood adds sparkle and ring.
Indian rosewood is also known for high sound velocity and broad range of overtones, strength and complexity in the bottom end and an overall darkness of tone in the rest of the range. Strong mids and highs also contribute a richness of tone to the upper registers. Indian rosewood has a thicker, more midrange overall coloration.
When used for necks, Indian rosewood can help fatten up the midrange.
||Spruce is the standard material for soundboards, the most commonly used species being Sitka. Its high stiffness combined with the lightweight characteristics of most softwoods, makes it a natural for high velocity of sound. A strong fundamental-to-overtone ratio gives Sitka spruce a powerful direct tone capable of retaining its clarity when played forcefully. This makes Sitka an excellent choice for top wood for players whose style demands a wide dynamic response and a robust, meaty tone. On the other hand, the lack of complex overtones in Sitka can produce a somewhat thin sound when played with a light touch - of course, depending upon the design of the guitar and the other choices of wood in its construction.
||Red spruce is relatively heavy, has a high velocity of sound, and the highest stiffness across and along the grain of all the top woods. Like Sitka, is has a strong fundamental, but also a more complex overtone content. Tops produce the highest volume, yet they also have a rich fullness of tone that retains clarity at all dynamic levels. In short, red spruce may well be the Holy Grail of top woods for acoustic steel-string guitars.
Maple, as a result of its greater weight and lower sound velocity, can be downright flat sounding, a blessing in disguise when a guitar is amplified at high sound pressure levels. This is why maple is the wood of choice for electric guitar tops. West coast big leaf maple is the softest and lightest of the maple family, with a wood grain that resembles waves. Aside from a visually breathtaking pattern, the wavy fibers of "curly" maple reduce the long grain stiffness and vibrate more freely. (This is the secret to the bright, clear powerful sound of the Parker Fly, a solid-body guitar made with a curly maple body.)
In acoustic guitar use, different species of maple, such as big leaf, sugar, and bearclaw tend to be more acoustically transparent due to their lower velocity of sound and high degree of internal damping. This allows the tonal characteristic of the top to be heard without the addition of significant tonal coloration.
Maple necks can impart a bright "poppy" tone that can do much to reinforce the top end of a large-bodied guitar.
||Alder is a lightweight wood that is highly resonant, producing a full rich tone. When used for solid-body construction, alder provides a very good low end and midrange with the best performance in the lower mid range. Alder also exhibits good high-end characteristics and sustain.
||Poplar is a stringy, dense, yet lightweight hardwood that is unusually resonant. Poplar, when used in solid-body electric guitars, has an exceptionally crisp sound, often described as "spirited" and "bouncy" - even "funky." Poplar guitars are ideal choices for players who favor single-coil snap and clean sound.
||Basswood is light, stiff, and stable, which makes it particularly effective for necks and bass instruments thanks to its excellent low- end response.
||Ebony, the traditional material found on the necks of violins, classical guitars, and high-end steel strings, has the lowest velocity of sound of all the woods commonly used and has definite damping characteristics. While not a problem for large-bodied guitars made of red spruce or Brazilian rosewood, it may be something to consider when designing smaller guitars, particularly those using less resonant tonewoods for tops and backs.
What is the benefit of a Handcrafted Acoustic-Electric?
Essentially, the earliest acoustic-electrics were simply acoustic guitars that had a standard magnetic pickup installed either in the soundhole or at the neck joint (as in the Gibson J-160E, popularized by the Beatles). Though these instruments could now be amplified, feedback was a constant problem, as was the compromised acoustic sound, as the pickups could not handle the complex high-frequency overtones produced by an acoustic.
In the late 1960s, all that changed when Ovation designed the piezoelectric bridge pickup. Rather than depending upon simple microphonics to increase volume, piezos amplified the actual vibrations of the guitar top and body and hence produced a more natural "acoustic tone." Over the years, many advances were made to help deliver a convincing acoustic guitar sound at concert hall volumes, with each manufacturer producing their own specific variation on what is now commonly called the "electro-acoustic guitar."
Given all that, the most important benefits of your modern acoustic-electric is the ability to play at concert hall levels and still retain the shimmering overtones of the acoustic, but without the feedback usually associated with high volume levels. Another benefit might be the ability to plug your guitar direct into your console, without the need for an expensive mic, not to mention a relatively noise-free environment to record it in.
Acoustic guitar body styles explained
This is actually a complex subject that could easily fill a book, as the various styles and sizes introduced by specific manufacturers have evolved over more than a century. However, the most significant change came in the 1920s, when guitars were designed to accept steel strings, rather than the traditional gut (or later nylon) strings.
Meanwhile, for those who wanted an acoustic with a richer bass response, Martin began building the so-called "dreadnought" models, which (trivia fans take note) were named after a famous British battleship. Many of Martin's most popular designs have been the D-sized instruments, from the relatively plain D-18 to the top-of-the-line D-45, with its ornate inlays.
From there, various manufacturers used these basic shapes and sizes as jumping-off points for other designs that included both sharp and rounded cutaways on the treble bout, as well as the unusual (but effective) Ovation guitars with their Lyrachord bowl-back designs.
Why are some handcrafted acoustic guitars more expensive than others?
This is another topic that could easily fill a book, but you can typically begin with the materials used in construction (such as premium timbers such as Sitka spruce, maple, mahogany and rosewood). As an example, highly figured maple backs and sides will certainly command higher prices than relatively plainer woods. What's more, certain woods are now in short supply, like Brazilian rosewood, so an instrument built using this particular wood will command a premium price.
Another important aspect in the price-to-performance ratio is whether the instrument is built by a skilled craftsman using hand-picked timbers. The best handmade guitars will take much longer to produce than those which are mass-produced in an assembly-line environment, since a gifted luthier will spend a great deal of time selecting each piece of wood used in construction, as each will play an important part in the complex tonal structure of the instrument.
Guitar pricing is also influenced by the quantity and quality of the ornamentation. As an example, Martin's D-50 K2 Deluxe features solid, highly figured flame koa for the front, back, and sides, with herringbone pearl rosette and grained Ivoroid body binding, a solid mahogany neck with solid black ebony fingerboard and mother-of-pearl and abalone heart inlays. List price? $47,500 (but you know the saying: If you have to ask, you probably can't afford it).
That's not to say that you can't get a great-sounding acoustic for a lot less money - a lot! It's just that some musicians (like the guys with the hit records) want the very best one-of-a-kind instrument. For us "normal" musicians, quality comes with a much lower price tag than that, though pinching pennies is not the way to get a great acoustic sound.
If you buy a premium quality acoustic guitar from a Guitar Manufacturer, you will more than be rewarded with superb tone and wonderful playability!