At first glance this might seem a curious concept, Swedish folksongs as sung – exceptionally so, let me say straightaway – mostly unaccompanied by a modest chorus through some of which jazz improvisations weave a separate counterpoint. Seven of the 15 numbers here are performed straight as a cappella choral numbers – mostly the more complex, modern items such as Rehnqvist’s The Fields of Light and Hillborg’s A Midsummer Night’s Dream, or those with a strong rhythmic profile already, such as Jan Sandström’s yoik Song to the Mountain Wind, or Lena Willemark’s arrangement of the traditional Wedding Song. These alone make a fine and varied programme, beautifully recorded in a spacious but not over-resonant acoustic.

Anders Widmark has had considerable success with jazz improvisations based on folk tunes and has collaborated previously with Allmänna Sången and Cecilia Rydinger Alin. That mutual understanding is manifest in the eight pieces where Widmark improvises, whether a prelude to the otherwise unaccompanied song, as with Rehnqvist’s kulning-inspired In Heaven’s Hall, or gentle accompaniments, as with his own arrangement of Herman Palm’s wordless vocalise. Purists will baulk at the liberties taken with some classics (“sacred cows”, even) of the Swedish repertoire, particularly Alfvén’s The Evening and Stenhammar’s Three Choral Songs. In the first of the latter in particular, Widmark’s additions break up and punctuate (some might opine disrupt) the musical flow.

All in all Widmark’s interjections, even at their most severe, are never against the spirit of the original pieces and do not mar them. Rather, his playing provides a new backdrop against which the individual works can be heard. As a programme – and this is definitely a disc to be played through in one sitting – the total effect is greater than the sum of its parts.