Sebastian Aguilera de Heredia belongs to the second generation of the organists who shaped the organ music of the Siglo de Oro, Spain’s golden age between 1550 and 1700. The generation around Antonio de Cabezon had established the central forms of the repertoire, above all the tiento, in which imitative sections alternate with virtuoso passages over sustained chords and dance-like episodes in triple time. Aguilera and Francisco Correa de Arauxo carried this legacy over to the modern Spanish organ, whose wind chests, divided into bass and treble, allowed a wealth of sound combinations. As organist of La Seo Cathedral in Zaragoza, Aguilera founded an Aragonese school of organists.
According to Martin Schmeding, Aguilera’s surviving organ works comprise eighteen compositions and an anonymously transmitted batalla attributed to him. Most are titled tiento, obra or vajo; four are devoted to the bass solo, among them the Registro baixo de 1° tom and the Dos vajos de 8° tono. A typical Aguilera tiento opens with one or more fugal sections whose figurations gradually grow denser; the second part stands in triple proportion to it and often takes up the main theme. Unusual rhythmic proportions and syncopated passages are characteristic. In the falsas, such as the Tiento de 4° tono de falsas, tied dissonances predominate, as in the Italian durezze e ligature; softly registered, they were predestined for use at communion (“sub communione”).
Among the more conventional pieces are the strict motet intabulation Discurso sobre los saeculorum and two versets each on the hymns Salve Regina and Pange lingua. Schmeding singles out the Obra de 8° tono alto. Ensalada as one of the most inventive and bizarre compositions of the Spanish organ Renaissance: true to the culinary sense of the word, Aguilera mixes polyphonic motet passages, virtuoso dances in triple time, echo passages, canzonas and batalla fanfares. A bonus track, audible only on SACD players, adds the Tiento de Batalla. 8° tono.
Gabriel Thomàs (1762–1836) built the organ for the monastery church in 1823. The origins of this Mallorcan master are unclear; according to Gerhard Grenzing, his craftsmanship, above all in making and voicing the reed stops, closely resembles the practice of Jordi Bosch. To tune the horizontal trumpets, panels are removed and the tuner leans out of the instrument; the pitch lies about a minor third below 440 Hz. Probably for lack of money while the monastic orders were being dissolved, the organ remained unfinished: the upper manual lacked the Quinzena, Dinovena and Simbalet, and the lower division was prepared only mechanically. Grenzing, who restored the instrument in 1981, added these stops in 1983, matching them to the original sound.
The recordings were made in April and May 2011 for an edition of six SACDs which also brings together works by Padre Antonio Soler, Domenico Scarlatti and José Lidon on the great Jordi Bosch organ in Santanyi and by Pablo Bruna, whom some musicologists count among Aguilera’s pupils, on the Mateu Bosch organ in Sencelles.