Polyphony and monophony in instruments harpejji and the Chapman stick). Multiphonics can be used with many regular wind instruments to produce two or more notes at once, although this is considered an extended technique. Explicitly polyphonic wind instruments are relatively rare, but do exist. The standard harmonica can easily produce several notes at once. Multichambered ocarinas are manufactured in a number of varieties, including double, triple, and quadruple ocarinas, which use multiple chambers to extend the ocarina's otherwise limited range, but also enable the musician to play more than one note simultaneously. Harmonic ocarinas are specifically designed for polyphony, and in these instruments the range
Quadruple reed Quadruple reed A quadruple reed is a type of reed by means of which the sound is originated in various wind instruments. The term "quadruple reed" comes from the fact that there are four pieces of dried palm leaf vibrating against each other, in pairs. A quadruple reed, such as the Thai pinai, operates in a similar way as the double reed and produces a timbre similar to the oboe. The Arabic "pii chawaa" is, "sometimes described as having a double reed though this is actually folded yet again, creating four layers of reed and thus requiring considerable lung power