Two French quartets, both the sole work for the ensemble by their respective composers, Debussy and Ravel.
The Ravel followed ten years after the Debussy, on which it’s clearly modelled. But the two quartets are also interesting in illustrating the differences between the two composers.
Debussy’s writing is much freer than Ravel’s whose leaning towards the constraints of neo-classicism make for a more clear cut architecture (as compared to the gorgeous blurrings of the Debussy).
That said, both composers are clearly equally concerned with the surface of their music and its beauty.