Tiento is also the name of one of the palos by which flamenco tunes are classified.
The tiento is formally extraordinarily diverse, more a set of guidelines than a rigid structural model such as fugue or rondo. Nearly all tientos are imitative to some degree, though not as complex or developed as the fugue. This has led to their being associated with the other embryonic imitative forms cited above. Similarly, it is difficult to assign a single texture to the form, since it underwent a considerable amount of evolution from its inception to its decline in the late 18th century. The earliest tientos (such as those of Cabezón) were stylistically quite close to the ricercare in their extended use of the strict, motet-style counterpoint. Later (especially in the works of Cabanilles), tientos would frequently alternate between the older style of strict counterpoint, and virtuosic, affective figuration typical of the toccata and some fantasias. The evolution of the form was in part conditioned by the evolution of the Spanish organ, and it eventually came to include several variants or sub-forms, several of which are listed below:
- Tiento de medio registro: A tiento making use of the split keyboard, frequently found on Spanish organs from the mid-16th century on. The split keyboard refers to an organ manual where ranks of pipes may be engaged for half the keyboard, as opposed to the entire compass, which is the norm. This enables the player to utilize different sounds on the same keyboard, generally a solo sound and an accompaniment sound, though occasionally two sounds of equal strength. The tiento de medio registro figures prominently in the oeuvres of Correa de Arauxo, Aguilera de Heredia, and Bruna.
- Tiento de lleno: The opposite of the tiento de medio registro; a tiento played on one sound (full register).
- Tiento de falsas: A tiento making frequent use of dissonance, so as to achieve particularly dramatic effect. “Falsas” refers to “false notes,” or dissonant tones not part of the current mode or key. It is similar to the Italian idea of Durezze e ligature (consonance and dissonance).
- Tiento pleno: an irregular tiento consisting of three sections: a prelude, fugue, and postlude. It has more in common with the German praeludium than with other tientos.