Although not as commonly experienced, resonator guitars still have a special place, and their distinctive sound is still very popular. Resonator guitars have a quality of sound quite unlike other guitars, and this is achieved through the use of a resonator fitted at the top of the guitar, in the middle. This resonator is made of metal, and its incorporation into the design of the guitar is not unlike that of the banjo, and there is certainly some similarity of sound quality between the two instruments.
Although the metal resonator fitted into the top of a guitar creates a sound quality or voice which is quite unique, its original purpose was not one of tone or quality, but merely volume.
Effectively, a resonator was introduced to aid amplification, with volume being the one main challenge affecting guitars as they grew from being solo instruments to ones played amongst a group of instruments or with a number of accompanying voices. Today the purpose of a metal resonator is largely redundant since electric amplifier units are so common and easy to incorporate into the set up of a guitar, and achieve a level and control of amplification which supersedes that of the resonator itself. However, its popularity lies heavily with the type of sound quality and distinct voice more than its amplification ability.
There are two types of resonator guitars, although both use cones situated at the top of the guitar to achieve the extra sound. The first type of resonator guitar is the one cone version, the second type is the three cone version.
The single or triple cone resonators are placed at the top, and the sound is fed through to them using a bridge. There are two types of bridges used. One is referred to as a biscuit, and is usually made of hardwood. The other type of bridge is referred to as a spider bridge, and is quite a bit larger than the hardwood biscuit, and always made of metal. The three cone resonator guitar always makes use of the larger spider bridge.
As far as playing a resonator guitar is concerned, the method is quite different from normal, traditional guitar playing methods. For example, with the type of resonator guitar known as a square neck guitar, so called because of the square cross section at the neck, the guitar is placed on the lap, or in front of the musician, face up. Quite often the player uses a slide, made of either glass or metal, to play the guitar, and although standard, round necked resonator guitars are held in a more traditional manner, the slides are still often used to play the instrument, and this is particularly the case in traditional blues music.
Another type of guitar often used for playing blues music is the twelve string guitar, which usually has nylon or steel strings which give a much crisper, brighter sound quality to the notes. The twelve steel strings are divided into six courses of two strings, and this method of construction or arrangement is very similar to that used for the mandolin or lute. Of the six courses, four are tuned according to octaves, but the highest pair are tuned together in unison.
Today the twelve string guitar can be found in electric form, although it is less commonly used in popular music, and still is more favored by those playing either blues, country and western or folk music. There is no such combination of a twelve string guitar and a resonator, despite both of these types of instruments being favored by jazz and blues musicians.
It is also interesting to note the distinctive quality of sound that each guitar type produces. It is often ignored or not understood by listeners of music that the type and construction of the guitar has every bit as much to contribute to the final sound and tone of the music as the notes and musician contribute themselves.