Becoming Sony’s No. 1 American string quartet is an impressive feat for even the Emerson String Quartet. Their first recording for Sony showcases four deeply committed musicians who play in every bar and in every manner as if they were one. Besides their being a fine quartet, the Emersons bring a positive frame of mind to Mozart, whom they consider more a colleague and a friend than a great composer. The relaxed speeds the Emersons take, the collaborative ensemble in which no one player stands out from the others (Philip Setzer plays first violin on tracks 1–4, and second violin on tracks 5–12; Eugene Drucker plays first violin on tracks 5–12, and second violin on tracks 1–4), even in the famous string of solo cellos, all of this and more bespeaks Mozart in full-out gallant mode.

Even so, there is no denying the heroic, open-hearted job cellist David Finckel does of assuming the role of Friedrich Wilhelm II. This is most apparent in K. 575, which is Mozart in his most ingratiating key of D major. The Emersons are outstanding in the other Prussians as well, although at times they seem baffled by the music’s admittedly enigmatic emotional signals and signs.

Recorded in LeFrak Hall at Queens College, the honest, clean sound catches the Emersons’ every nuance and gleam.