Tiento de Falsas de 6to Tono

Tiento (Spanish pronunciation: [ˈtjento], Portuguese: Tento [ˈtẽtu]) is a musical genre originating in Spain in the mid-15th century.

It is formally analogous to the fantasia (fantasy), found in England, Germany, and the Low Countries, and also the ricercare, first found in Italy.

By the end of the 16th century the tiento was exclusively a keyboard form, especially of organ music. It continued to be the predominant form in the Spanish organ tradition through the time of Cabanilles, and developed many variants. Additionally, many 20th-century composers have written works entitled "tiento".

A "Tiento de falsas" Is 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).

Another fine and totally different recording of this work has been done by Hoofdwerk on the Palma organ.
The link is here:
http://www.contrebombarde.com/concerthall/music/5723