The pan flutes are a group of musical instruments based on the principle of the closed tube, consisting of multiple pipes of gradually increasing length (and occasionally girth). Multiple varieties of panflutes have long been popular as folk instruments. They are considered to be the first mouth organ, ancestor of both the pipe organ and the harmonica. The pipes are typically made from bamboo, giant cane, or local reeds. Other materials include wood, plastic, metal and ivory.
The pan flute is named after Pan, the Greek god of nature often depicted with such an instrument.
The pan flute's tubes are stopped at one end, at which the standing wave is reflected giving a note an octave lower than that produced by an open pipe of equal length. In the traditional South American style, pipes are fine-tuned to correct pitch by placing small pebbles or dry corn kernels into the bottom of the pipes. Contemporary makers of curved Romanian-style panpipes use wax (commonly beeswax) to tune new instruments. Special tools are used to place or remove the wax. Corks and rubber stoppers are also used, and are easier to quickly tune pipes.