The marimba is a percussion instrument consisting of wooden bars struck with mallets to produce musical tones. While its roots are in Africa—where instruments like the balafon used gourds as resonators—the modern marimba developed in Central America, specifically Guatemala and Mexico, during the 16th and 17th centuries. Underneath each wooden bar (usually made of rosewood) is a resonator pipe, traditionally made of bamboo or gourds and now typically made of aluminum. These resonators are tuned to the frequency of the bar, amplifying the sound and giving it a warm, woody resonance. A unique feature of traditional Central American marimbas is the 'charleo,' a buzzing sound produced by a thin membrane placed over a hole in the resonator. In modern classical music, the marimba has evolved into a solo virtuoso instrument, often requiring the player to hold two mallets in each hand to play complex chords and melodies simultaneously.