Delores Stevens, pianist and artistic director of the Martha’s Vineyard Chamber Music Society, will join a quintet of musicians from the Music from Salem festival series in two concert performances July 21 and 22.

After a genre-stretching foray into jazz chamber music with Billy Childs and the Infiniti Brass, the society, now at the midpoint of its five-week season, returns to its romantic classical roots with a program of music by Felix Mendelssohn and Cesar Franck.

At the Old Whaling Church in Edgartown on Monday, and again at the Chilmark Community Center on Tuesday, the society will perform Mendelssohn’s First String Quintet, opus 18, in A Major. Melodically inventive, energetic and unabashedly lyrical, the work was composed in 1826, when Mendelssohn was just 17, and revised in 1832. It’s a genial piece, rich with melody and counterpoint but easy and graceful rather than philosophical or conflicted.

It was written for piano, two violas, two violins and cello, which explains the roster of artists who will be performing here: violists Werner Dickel and Lila Brown (a cofounder of the Music from Salem festival); violinists Ulrike-Anima Mathe and Kjell-Arne Jorgensen, and cellist Claus Kanngiesser.

Also on this week’s concert program is the Piano Quintet in F minor by Franck, one of three chamber music masterpieces the composer wrote in the last years of his life. The quintet, composed in 1879, is seen by some critics as a watershed moment for chamber music, both for its originality and its broad emotional range. Like many of Franck’s works, it involves a “cyclic” form of composition, with interrelated themes unifying its three movements.

Both this week’s performances will be given at 8 p.m. Admission is $30, and students are always free.