Allan Pettersson's Symphony No. 15 is characterized by a high degree of tension right from the striking opening: brief, emphatic chords from horns and trombones above the tremolo of a side drum. Soon an expressive melodic subject is heard from the first violins, followed by contrasting rapid scales - at which point Pettersson has presented the greater part of the symphony's building blocks. Like so many of the composer's symphonies, the 15th is in one movement, but with clearly defined sections. It was completed in 1978, two years before Pettersson's death, and was followed in 1979, by the sixteenth symphony, the last work that the composer submitted for performance. Only later did it become known that Pettersson had also been working on a Viola Concerto - a work that, if not fully completed, was so far advanced that it has been accepted as part of his ouvre. It is presented here by the Swedish violist Ellen Nisbeth, who also performs one of Pettersson's very earliest compositions - a Fantaisie pour alto seul, dated June 1936, when the composer himself was about to embark on a career as violist. On this the tenth disc in their acclaimed Pettersson cycle, the Norrköping Symphony Orchestra and Christian Lindberg bring their combined expertise to bear on the orchestral scores.