The document discusses three musical instruments: Mandora, a type of lute; Dobro, a resonator guitar; and Udu, an African drum from Nigeria that produces a unique bass sound when its large opening is struck but its entire body can be played with fingers.

1. Mandora: a type of lute
Dobro:a resonator guitar
Udu: an African drum used in Nigeria. Udu means vessel. It has a unique bass sound by
hitting the big whole, but the whole corpus can be played by fingers.