The first movement of this 4th Symphony begins with an ostinato that gradually accumulates different elements that build the basic harmonic scheme. Various more melodic elements then enter and seem to struggle with the ostinato.
The second movement opens with a long, expressive duet between the harp and the solo flute, a duet punctuated by delicate interventions by other instruments. The action, led by the strings, then becomes more dramatic and finally dreamlike.
The third movement is based on the lydian E flat scale and develops a melodic cell in loop. Gradually, the instruments go from bass to treble, colored by percussion, to reach an intense and fortissimo climax.
The fourth movement relies on an obsessive ostinato to lead to a vertiginous resolution.