The exceptional trio of concerts sponsored by the Foundation for Advanced Education in the Sciences this month continued on Sunday afternoon. Just like last Sunday’s concert and the final installment next Sunday, this concert at Bethesda’s Congregation Beth El by the Auryn Quartet plus violist Roger Tapping combined two Mozart string quintets with one Britten string quartet. The result after three weeks will be an unusual achievement, a complete cycle of both sets. One or the other would be worth hearing: together, the program should be irresistible.

This week’s concert began with the other relatively early quintet, K. 406 in C minor, which Mozart reworked from a wind serenade, K. 388, from 1782. It is a somber work with a few sunny turns and an abundance of contrapuntal complexity. After an earnest unison opening and dark first theme in the first movement, the Auryn Quartet and Tapping handled the marvelous transition to the major-key second theme — one of those light-filled moments — with grace and appropriate vigor in the closing theme. In the development, we hear Mozart experimenting again with Baroque suspensions and harmonic twists, lovely dissonance that echoes many similar moments in the early Mozart quartets and divertimenti. The rewrite of the second theme in the recapitulation, which must end in minor, is just as memorably a turn back to the shadows. A divinely melancholy second movement and an austerely canonic menuetto and trio (the latter an improbable inverted canon) followed, capped off by the variations of the final movement, alternately enigmatic and joyous.

Image of excerpt from Mozart string quintet in C major, K. 515, first movement