Quartetto Italiano for the Beethoven middle and late quartets
Also great for the late Schubert quartets.
Borodin String Quartet for the Shostakovich quartets. You probably want the second set from the 1980s.
Favorite Classical String Quartets
When I started listening to Classical Music as a teenager over 50 years ago I quickly became seduced by the sounds of a string quartet. My school library had a Seraphim 3LP set of Beethoven Middle Period Quartets with the Hungarian SQ (this was in stereo; they had recorded them in mono as well). Op. 59/1, the first of the Razumovsky Quartets, was my seductress: those long soulful cello lines, with the viola weaving in and out, the violins then sweetly taking over the main themes, and then all the instruments trading places-I was hooked.
59/3 has a second movement dominated by the cellist who sounds like a jazz walking bass, and that furious fugal finale. The Harp Quartet in that with its flying pizzicatos was another revelation.
Beethoven’s late quartets are another thing entirely, and took a few generations for nineteenth century listeners to absorb. Mozart and Haydn invented the genre and a lot of their best music is in their quartets.
The aforementioned Classical Period composers are generally thought to have represented the apex of the genre, but I have always been fascinated by Dvorak, Borodin, and Shostakovich, all of whom seemed to luxuriate in the special sonic world of the string quartet.
Other favorites?
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