 | This article needs additional citations for verification. (January 2019) |
 Single cone resonator with metal body | |
| String instrument | |
|---|---|
| Other names | Dobro |
| Hornbostel–Sachs classification | 321.322 |
| Inventor(s) | John Dopyera |
| Developed | 1920s |
| Volume | Medium |
| Attack | Fast |
| Related instruments | |
| Acoustic guitar | |
| Builders | |
|
Dobro, National, National Reso-Phonic, Del Vecchio-Dinamico | |
A resonator guitar or resophonic guitar (often erroneously called a "Dobro"[1]) is an acoustic guitar that produces sound by conducting string vibrations through the bridge to one or more spun metal cones (resonators), instead of to the guitar's sounding board (top). Resonator guitars were originally designed to be louder than regular acoustic guitars, which were overwhelmed by horns and percussion instruments in dance orchestras. They became prized for their distinctive tone, and found life with bluegrass music and the blues well after electric amplification solved the problem of inadequate volume.
Resonator guitars are of two styles:
- Square-necked guitars played in lap steel guitar style (also called a dobro)
- Round-necked guitars played in conventional guitar style or steel guitar style
There are three main resonator designs:
- The tricone, with three metal cones, designed by the first National company
- The single-cone "biscuit" design of other National instruments
- The single inverted-cone design (also known as a spider bridge) of Dobro brand instruments and instruments that copy the Dobro design[2]
Many variations of all these styles and designs have been produced under many brand names. The body of a resonator guitar may be made of wood, metal, or occasionally other materials. Typically there are two main sound holes, positioned on either side of the fingerboard extension. In the case of single-cone models, the sound holes are either both circular or both f-shaped, and symmetrical. The older tricone design has irregularly shaped sound holes. Cutaway body styles may truncate or omit the lower f-hole.
- ^ Cite error: The named reference
:0was invoked but never defined (see the help page). - ^ The term dobro is used to refer to any single-resonator guitar, or resonator guitars in general, but Dobro® is a trademark, registered since 1993 by the Gibson Guitar Corporation.