Flamenco guitar
Tambour (also called tambor, tamboro or tambora, written in music as tamb.), is a technique in Flamenco guitar and classical guitar that emulates the sound of a heartbeat. The player uses a flat part of the hand, usually the side of the outstretched right thumb, or also the edge of the palm below the little finger, and sounds the strings by striking them rapidly just inside the bridge of the guitar. Duration can be from a single articulation to an extended drum roll-like tremolo. If performed incorrectly, the effect is similar to a right-hand apagado, or dampening of the strings.