¶ … Acoustic Guitar Although not nearly as controversial as saxophones upon their introduction, acoustic guitars have nevertheless had a lasting impact on the world of music since their invention 400 years ago. Noted for their pleasant tonality and frequently beautiful appearance, acoustic guitars remain a mainstay of several music genres such as pop and folk, and provide many newcomers to music with their first experience playing an instrument. Given their increasing popularity in recent years, it is clear that acoustic guitars are here to stay, but many people may not appreciate their lengthy heritage and the craftsmanship required to build such an instrument. To this end, this paper provides an overview of the history of acoustic guitars, followed by a description of how they are made; a summary of the research and salient findings will be provided in the conclusion.

Review and Discussion

History of Acoustic Guitars. In 1944, Muddy Waters enthused that the acoustic guitar "is a voice like no other. The guitar is a miracle. Out of the strings and the frets comes this personality whether a blind man from Texas [Blind Lemon Jefferson] or a Gypsy from Belgium [jazz acoustic guitar pioneer Django Reinhardt] of a unique human being" (Bennett & Dawe 28). This enthusiasm for the instrument is not uncommon, nor is it even as recent as the mid-20th century. In fact, the acoustic guitar, in its various permutations has enjoyed a great deal of popularity from a number of centuries. While the acoustic guitars that are commonly used today have some fairly recent innovations, the basic form of the instrument has not changed all that much since it originated, most likely, in Spain at some point during the early 16th century (Guitar 1).

The modern acoustic guitar was derived from the guitarra latina, an instrument dating from the late-medieval era and sporting a waisted body with just four strings (Schreiner 133); in addition, these early acoustic guitars were narrower and deeper than their contemporary counterparts, and there waists were less pronounced (Guitar 1-2). According to Gangwere, the term "guitar" is generally applied to any of a variety of plucked string instruments dating from the Middle Ages and the Renaissance; these are believed to have derived from both the aforementioned guitarra latina as well as the guitarra morisca (202). These early guitars only had four courses of strings (three double, the top course single, that ran from a pegbox that resembled a violin to a tension bridge that was glued to the soundboard, or the instrument's "belly"); consequently, the bridge withstood the direct plucking of these four strings (Guitar 3). A number of changes over the years, discussed further below, resulted in the instrument that is popularly known today.

By the early 20th century, the acoustic guitar had assumed a high degree of prominence in the United States, particularly among those jazz, blues and folk artists who subscribed to the "myth of acousticity" that emerged during this period. According to Bennett and Dawe (2001), the myth of acousticity concerned the specific characteristics of the guitar that contributed to its rich sound, in sharp contrast to the electric guitar sound that was becoming popular: "This myth pits the supposedly superior, authentic, 'natural' sound of the traditional wooden guitar, as perceived by sensory media (ears and eyes), against the inferior amplified sounds of guitars employing electronic magnetic pick-ups, sound processors, and amplifiers" (29). The second part of the myth concerned its cultural implications, as the acoustic guitar represented its place in the instrument hierarchy, with the electric versions being viewed as poor substitutes that had not yet earned their place in the respectable musician's repertoire. In this regard, Evans (1997) points out by the early 1940s, the "tonal-purity-of-the- acoustic-guitar" debate could best be understood as a legacy of cultural hierarchy, or a "well-worn High Culture aesthetic for instruments used in the performance of cultivated art music,"...

By the late 1940s, most blues singers accompanied themselves on the steel-string acoustic guitar (Friedlander 19). The 1960s witnessed an explosion in the popularity of acoustic guitars, due in large part to rock and roll bands such as the Beatles and their peers who used them to good effect (Rowley 45). By the turn of the 21st century, the acoustic guitar had become a standard feature in various pop, rock, jazz and folk festivals across the country, the best-known being the Newport Folk Festival, Woodstock and the Mariposa Folk Festival; these events included blues artists where acoustic guitars were virtually ubiquitous and the participants believed that the music being created on these instrument was a democratizing influence on society (Bennett & Dawe 29).
The Manufacture of Acoustic Guitars. While the manufacture of acoustic guitars today benefits from some innovations in technology that were not available to instrument-makers from the 16th century, from 1600 to 1900, the acoustic guitar experienced a number of significant changes in its manufacture that helped to create the form of the guitar that is popularly known today (see Figure 3 below). For example, instrument-makers added a fifth course of strings at some point prior to 1600, and by the late 18th century a sixth course was added (Guitar 3). During the late 17th century, the double courses of strings were replaced by single strings. In addition, sometime around 1600, the pegbox, previously constructed in a violin-shape, was replaced with a flat, head with rear tuning pegs that was slightly reflexed; further, at some point in the 19th century, instrument-makers began replacing the tuning pegs with metal screws (Guitar 3-4).

During the 18th century, the gut frets that had been tied on were replaced with built-on ivory or metal frets. Likewise, earlier versions had the fingerboard flush with and ending at the instrument's belly with several metal or ivory frets placed directly on it; however, during the 19th century, the fingerboard was raised above the level of the belly slightly and extended across it to the edge of the sound hole (Guitar 4). According to Marshall Brain (2005), "The [sound] hole is normally round and centered, but F-shaped pairs of holes, as in a violin, are sometimes seen. Attached to the soundboard is a piece called the bridge, which acts as the anchor for one end of the six strings. The bridge has a thin, hard piece embedded in it called the saddle, which is the part that the strings rest against" (3). The sound hole from a Gibson SJ200 acoustic guitar is shown in Figure 1 below:

Figure 1. Sound hole in a Gibson SJ200 acoustic guitar body.

Source: Brain 4.

As can be seen in Figure 2 below, the vibration of the strings travels through the saddle to the bridge to the soundboard, causing the entire soundboard to vibrate; the hollow body of the guitar provides the soundbox that serves to amplify the vibrations of the soundboard:

Figure 2. Soundboard and components.

Source: Brain 4.

At some point during the 19th century, the acoustic guitar's body was also changed in a successful attempt to increase its sonority. After these changes were made, the instrument became broader and shallower, with an extremely thin soundboard. Internally, the transverse bars reinforcing the soundboard were replaced by radial bars that fanned out below the sound hole (Guitar 4). The neck had been set into a wood block in the past, but was now manufactured into a brace, or shoe, that projected a short distance inside the body and was glued to the back; this feature provided extra stability against the pull of the strings (Guitar 4-5). The 19th-century innovations have been primarily credited to the work of Antonio Torres. According to Schreiner (1990), "The kind of guitar developed by Antonio Torres (1817-1892), a guitar builder from Almeria, already had a feminine form and four strings, resembling the modern guitar.…