The body of a traditionally shaped electric guitar (roughly 12 to 13 inches at the lower bout) is usually cut from two pieces of wood that have been glued together with the end grain facing in opposing directions. This is both for the structural integrity of the body (to help avoid cupping) and because raw tone wood that has been cut 13 inches wide is difficult to find and procure.
On an acoustic guitar the body is made up of 3 primary components: the top, the sides and the back. The body is its own natural amplification on an acoustic guitar, and the top is responsible for the vast majority of the tone and volume.
On a solid body electric guitar, some believe that the body is just an aesthetic concern. Ned Steinberger produced his famous graphite electric guitars with no real body to speak of, that relied nearly entirely on the electronics to shape the sound. Alas, wood versus synthetic material is a very subjective discussion and an argument for another day.
We at Bertram Guitars feel that wood types most certainly help shape the tone of an electric guitar. If one were to assign a tonal range to wood types using density (hardness) as the constant, generally speaking, the denser the wood, the brighter the tone. The reverse is also true that the softer the wood, the warmer the tone.
The top of an acoustic guitar is the key component of its sound. A solid top acoustic guitar will sound better than a laminate top guitar 9 times out of 10. This is because glue is a barrier to vibrations, and although laminate tops are significantly stronger than solid tops, the tone of the guitar usually suffers when laminates are used on accoustic guitars.
The 2 most popular woods for acoustic guitar tops are Spruce and Cedar. Generally speaking, Spruce produces a bright sound and Cedar produces a warmer sound by comparison. Spruce is most often preferred by guitarists who use picks (flat-pickers) and Cedar is most often preferred by players who use their fingers (finger-pickers).
When speaking of the top on a solid body electric guitar, it is most often in reference to a piece figured Maple, Koa or other exotic wood that is glued to the thicker back of the guitar body. Often a finish or stain is aplied to bring out the natural figuring.
A Maple top with a Mahogany body is classic pairing of complimentary tonewoods. The Maple top, whether flamed or not, will add high end bite to the rich dark tone that Mahogany produces. This is done for both cosmetic and tonal purposes, and hand-built guitars with highly quilted, flamed, spalted or burled tops can fetch thousands of dollars on the boutique guitar market.
When speaking of the sides on a solid body electric guitar it is usually in reference to the angle of the cut or bevel. Solid body electric guitars don't have sides is the same sense that acoustic gutiars have sides. The Sides of an acoustic guitar are sparate pieces of wood that are molded to form and then attached to the top and the back. The sides may be solid or laminated. Remember that laminates provide strenght and stability, but solid wood will almost always produce better tone than laminated wood.
The back of both solid body electric and acoustic guitar is often prized for the exotic wood employed in its construction. Tonally, espcially for acoustic guitars, it is just another component of the guitar, having about as much importance as the sides. It is the top, remember, that is responsible for the lion’s share of an acoustic guitar’s tone.
Binding is a strip of plastic, sometimes a multiple layer laminate, that is glued into a rabbit cut ridge all around the edges of the top, and sometimes also the back of the guitar. Usually binding is found on more expensive models and often the necks and headstock are bound as well as the bodies. The primary reason for binding is for protection, but in most cases binding is mostly an aesthetic preference.
The neck of the guitar must be stable and true. A stable neck and a solid neck joint are essential in a good guitar. A neck can be glued or bolted onto a body, or it may even run all the way through the body, as in the case of neck-through-body guitars. The neck of an acoustic guitar is often glued onto the body but some companies like Taylor bolt the neck onto the body. This eleimates a layer of glue and thus eliminates a layer of vibratory resistance.
The Headstock is where the strings attach to the tuners. It is most often where a company brands their guitars. Many famous guitars are recognizable from their headstocks as well as their finshes or electronic configurations.
The truss rod is a steel bar fitted inside the neck, below the fingerboard, that is anchored at each end. It may be tightened or loosened using an Allen wrench to straighten or bow the neck. It is used to offset the tension created when the guitar is strung and to help stabilize the neck. The truss rod adjustment hole on an electric guitar is most often located at the base of the headstock, beneath a truss rod cover. Acoustic gutars are often adjusted at the base of the neck, inside the soundhole on the top.
Tuners are used to tighten and loosen the strings and are most often located on the headstock. Certain tremolo guitars have tuners at the tail rather than the headstock because they lock the strings in place at the nut (top of the neck) to help keep the strings in tune.
The fretboard is glued to the top of the neck. A guitar fretboard usually has 21, 22 or 24 frets, although there are of course variations. Most acoustic guitars aren’t intended to be played high on the neck so there aren’t as many frets because they aren’t particularly needed. Some Parlor style (small bodied) acoustic guitar fretboards only have 18 or 19 frets.
A fret is piece of semi round wire that is hammered into the fretboard in mathematically determined positions, so that a specific note is played when a string is held against it. Each fret is a musical interval of one-half step. Move one fret up the neck and you've moved up the chromatic scale one half step. Move twelve frets and you’ve moved one octave. A 24 fret neck is a 2 octave neck.
The nut is the piece of bone, graphite or other material that sits at the top of the neck, right below the headstock. It has six grooves for the strings, and holds them above the frets over the fretboard. The nut is traditionally made of bone, but today graphite is often used.
There are basically two types of guitar pickups: the Single Coil and the Double Coil a.k.a. the Humbucker. One could argue that the Single Coil pickup is best represented by the Fender Stratocaster and the Humbucker pickup by the Gibson Les Paul.
Traditionally, Single Coil pickups produce a hum (electronic noise) when plugged into an amplifier. Their tone is (generally speaking) thinner than a Humbucker. Humbuckers have a full, fat tone and produce no hum when plugged into an amp. Humbuckers are well suited to heavy, distorted sound because of their superior output and hum canceling characteristics. The Humbucker (Double Coil) pickup was created when someone, somewhere, sometime, discovered that when you place two Single Coil pickups next to each other, the hum cancels out, hence the name Hum-bucker. Each of these two styles of pickup has distinct tonal qualities that make it attractive, and each is available in wide output ranges.
The Bridge is where the strings pass over at the bottom of the guitar. Acoustic guitars usually utilize a one-piece bone or graphite bridge that is perpendicularly offset for proper intonation and set into a wooden tailpiece. The position of the bridge is vital in the intonation of the guitar.
Bridge position is dictated by the scale of the neck. The distance to the 12th fret when measured from the nut should be precisely 12.5 inches and the distance from the 12th fret to the centerline of the bridge should be 12.5 inches. Pretty simple, huh? For a 25 inch scale neck, the distance from the nut to centerline of the bridge should be 25 inches. Remember though that the bridge must be slightly offset perpendicular to compenstate for the traditional shortcommings of guitar tuning.
Saddles are almost never present on an acoustic guitar. The Saddles are the individual (hopefully moveable) parts on which the strings actually rest on the bridge of an electric guitar. These are extremely important in intonating your electric guitar.