A resonator dulcimer is an Appalachian dulcimer

Appalachian dulcimer

The Appalachian dulcimer is a fretted string instrument of the zither family, typically with three or four strings. It is native to the Appalachian region of the United States...

 which features a metal resonating cone inset in the body, which receives and acoustically amplifies the vibration of the strings.

Unlike resonator guitar

Resonator guitar

A resonator guitar or resophonic guitar is an acoustic guitar whose sound is produced by one or more spun metal cones instead of the wooden sound board . Resonator guitars were originally designed to be louder than conventional acoustic guitars which were overwhelmed by horns and percussion...

s, resonator ukulele

Resonator ukulele

A resonator ukulele or "resophonic ukulele" is a ukulele whose sound is produced by one or more spun aluminum cones instead of the wooden soundboard...

s, and resonator mandolin

Resonator mandolin

A resonator mandolin or "resophonic mandolin" is a mandolin whose sound is produced by one or more metal cones instead of the customary wooden soundboard . These instruments are sometimes referred to as "Dobro mandolins," after pioneering instruments designed and produced by the Dopyera Brothers,...

s, the resonator dulcimer was never commercially produced on a large scale.

History

The earliest attested resonator dulcimer was built by dulcimer luthier Homer Ledford

Homer Ledford

Homer C. Ledford was an instrument maker and bluegrass musician from Kentucky who specialized in making dulcimers....

, who called it a "dulcibro" (portmanteau of "dulcimer" and "dobro

Dobro

Dobro is a registered trademark, now owned by Gibson Guitar Corporation and used for a particular design of resonator guitar.The name has a long and involved history, interwoven with that of the resonator guitar...

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