The instrumentation of a kabuki dance piece varies according to the needs of the form and the dance. The singer and the shamisen perform the melodies; the use of the drums and flutes is more complex. Lyrical sections are often supported by the bamboo flute. The nō flute is used to play patterns totally unrelated to the shamisen melody: it sets the mood or, with the taikostick drum, performs parts of patterns derived from nō. The taiko itself is used to play either named, stereotyped patterns originating in the nō tradition or units created for kabuki. The latter tend to reinforce the rhythm of the shamisen music, while the former sound ‘out of synchronization’ with it, although they match the melody of the nō flute if it is also being played. Such deliberate disjunction helps to create the necessary sense of forward motion and progression. The two tsuzumi drums are similarly used; often they directly support the shamisen rhythm in a style called chirikara, named after the mnemonics by which the music is learnt. When the drummers play patterns derived from nō, they, too, sound out of step with the main melody. Sometimes, therefore, the tsuzumi and shamisen are in one rhythmic conjunction, while the taiko and nō flute are tonally, melodically and rhythmically in a different cycle. This can be called a ‘sliding door’ effect, for the units each have a fixed internal structure but do not necessarily begin and end together. The effect is analogous to that of the harmonic settings of Western traditional music, although the sound is very different. As in Western harmonic progressions, the tensions are released at main cadence points.