Festina lente (More haste, Less speed) is a 1988 composition by Estonian composer Arvo Pärt. It is scored for string orchestra and harp. It uses layering to explore the musical ideas, by allowing the violas to take the melody, the violins to take it at double the speed and the basses to take the melody at half time.
References
Festina lente (Pärt) Wikipedia(Text) CC BY-SA