The hollow-body acoustic guitar made its mark on the music world long before the electric guitar. Apart from the natural sound produced string vibrations bouncing inside the hollow cavity that makes up the guitar’s body, an acoustic guitar has traditionally not used amplification. This guitar, which uses an open cavity to produce sound, is a versatile and portable instrument that is popular among musicians of all genres. Most acoustic guitars do not come with any electronics to produce amplification, though more and more of these guitars are coming stock with pickups that allow the guitar to be played with or without an amplifier. The acoustics of the guitar body are used instead, allowing sound to bounce around inside the hollow cavity and escape through a sound hole beneath the strings.
The following is how it works: when the strings are struck, they vibrate and produce sound. However, because strings can only vibrate so much and produce so little sound, this guitar is designed to allow the strings to vibrate through the bridge and, in turn, the soundboard –– or face –– of the guitar. The hollow body of the guitar then amplifies this vibration, which is then released through the sound hole. The sound is created naturally and does not require any external amplification, though pickups are available to enhance the guitar’s sound in the same way that electric guitars do.
An acoustic guitar’s appearance is also noteworthy: the most common body style is known as a dreadnaught, and it can include a cutaway so the player can access frets closest to the guitar’s body. Around the sound hole, the guitar may have different decorations, such as ornate pick guards or rosettes –– decorative inlays.
To produce a desirable and distinct sound, the acoustic guitar must be meticulously constructed. The body of a guitar, also known as a luthier, is constructed using a system of braces, and the materials used must be carefully chosen for their sound transmission qualities. Luthiers also choose their binding materials carefully, selecting glues and finishes that will not degrade the instrument’s overall sound quality.
The sound produced the acoustic guitar can be influenced a variety of factors. The classical guitar, for example, uses a similar sound production method but with nylon strings rather than steel strings, resulting in a less sharp sound that is more commonly heard in classical music. Woods, glues, strings, body shape, and a variety of other factors can all influence tone.