The third volume of the Danish String Quartet’s ongoing Prism series, which shows how the radiance of Bach’s fugues is refracted through Beethoven’s quartets to illuminate the work of later composers. “Beethoven had taken a fundamentally linear development from Bach,” the Danes note, “and exploded everything into myriadsof different colours, directions and opportunities – much in the same way as a prism splits a beam of light.” Here the quartet follow the beam from Johann Sebastian Bach’s Fugue in c-sharp minor through Ludwig van Beethoven’s String Quartet no.14 to Béla Bartók’s String Quartet No.1.