In music, "ostinato" (Latin obstinatus: "obstinate") is a constantly repeated sequence of notes. A constantly repeated bass motif is perfect for improvisation - which in turn inspired many Baroque composers to write numerous masterpieces. Gunar Letzbor has put together a splendid programme from this fund of pieces, including the well-known Ciaconnas by Bertali and Schmelzer and two ostinato-dominated sonatas by the violin virtuoso Biber, but also works by lesser-known composers such as Georg Arnold, Heinrich Dˆbel and Johann Josef Vilsmayr. In the question of the continuo instrumentation, the Ensemble Ars Antiqua Austria breaks new ground: according to new research, the magnificent Salzburg court, where Biber was Kapellmeister, had a special continuo accompaniment: for this magnificent instrumentation with lute, chitarra attiorba and colachone, the ensemble had the instruments specially reconstructed and now lets the "Salzburg lute continuo" be heard again on this recording.