Christian Orthodox monk playing the board bell.

Toaca (Board bell) is a musical instrument of percussion in the idiophone class used in Orthodox liturgy. Board bell and bells are the only musical instruments accepted by the Orthodox Church .

The board bell is most often made of a wooden board or sometimes a thick brazed iron plate, one or two hammers are used for percussion at the hours set for prayer. Percussion is done rhythmically and, depending on the place where the wood or metal plate is struck, sounds of varying heights can be obtained, thus creating a simple melodic line.

Is estimated that it was introduced in Romania in the 6th century.