Saltarello takes its name from a fast Italian dance in triple time, documented in the 14th century and still alive as a folk dance. Viola player Garth Knox uses it as the title of a programme that runs from the 12th century to the present day. His point is that the line between art music and folk music, and between early music and new sounds, is thin and often arbitrary. Hildegard von Bingen, Machaut, Dowland, Purcell and Vivaldi share the disc with Kaija Saariaho, with Knox himself and with anonymous dance tunes.

Knox, Irish-born and for many years the violist of the Arditti Quartet, plays fiddle, viola and viola d'amore. Cellist Agnès Vesterman joins him in the Baroque and Renaissance pieces, percussionist Sylvain Lemêtre in the medieval and traditional ones. The album was recorded in December 2009 at the Auditorio of Radiotelevisione svizzera in Lugano, in collaboration with RSI Rete Due. Manfred Eicher produced, with Stephan Schellmann as engineer. Knox arranged most of the material and wrote the liner notes, following his earlier ECM album D'Amore.

The opening Black Brittany puts the viola d'amore on a blend of the traditional Black Is the Colour of My True Love's Hair and Johnny Cunningham's Leaving Brittany. Vivaldi's Concerto in D minor RV 393 is played as a duo with cello. Saariaho's Vent nocturne, for viola and electronics and written for Knox, is split in two halves that frame Dowland's Flow My Tears. In Sombres miroirs and Soupirs de l'obscur, breath noises, tremolo and harmonics merge with electronic wind sounds. Knox's own Fuga libre, for solo viola and dedicated to the memory of Ruth Inez Apthomas, joins dense counterpoint to theatrical gestures. The record closes with three 14th-century dances for fiddle and percussion and Pipe, Harp and Fiddle, built on Irish traditional tunes.

Writing in MusicWeb International in 2012, Dominy Clements called it "a very fine recording and a very creatively constructed programme". He praised the rich ECM sound and singled out the Purcell, where the viola d'amore adds a melancholy tone as an equal partner to the cello. He found more melodic shape in the Saariaho than its description suggests. His verdict: "this is a journey very much worth taking."

CD edition of ECM New Series 2157, first released on 16 March 2012.