Pennsylvania Sinfonia Orchestra presents the second of its four “Valley Vivaldi Summer Series” chamber music concerts, 7:30 p.m. July 10, Christ Lutheran Church, 1245 W. Hamilton St., Allentown.

The program includes intimate and spirited instrumental works by composers from the late 17th and early 18th centuries.

Pennsylvania Sinfonia violinist Rebecca Brown has the solo role in Bach’s Concerto in E for violin and strings, BWV 1042. Principal trumpeter Lawrence Wright performs the Sonata in D à 5 for trumpet and strings by Grossi.

Both featured musicians are frequent soloists for the Valley Vivaldi summer series.

Brown is principal second violin for the Sinfonia, and also performs regularly with the Bach Festival Orchestra, Allentown Symphony and chamber music group Satori.

In addition to the Pennsylvania Sinfonia Orchestra, Wright is a member of the Bach Festival Orchestra, Allentown Symphony, and co-principal trumpet of the Philadelphia Brass.

Brown and Wright are joined by colleagues Mary Ogletree and Simon Maurer, violins; Agnès Maurer, viola; Elizabeth Mendoza, cello; Nancy Merriam, bass; Robin Kani, flute, and Allan Birney, harpischord.

The concert opens with Vivaldi’s Concerto for strings in G minor, then Concert III by Rameau.

In addition to the Bach Violin Concerto, the ensemble will play the Ricercar à 6 from Bach’s “Musical Offering.” The movement, a six-voice fugue or canon, is Bach’s response to a challenge given to him in 1747 by Frederick the Great of Prussia. Frederick gave Bach, a master improvisationalist at the keyboard, a single theme on which to base the three-part fugue. When Bach performed that with relative ease, Frederick went on to ask for a six-part fugue, thinking it an impossible task.

Bach took the assignment home, and within a couple months produced the “Musical Offering,” a series of 10 increasingly complex yet musical canons for keyboard. At “Valley Vivaldi,” each of the six voices will be performed by a different instrument (strings, flute and harpsichord), making it perhaps a bit easier to hear how Bach integrates and interweaves the single, complicated theme.

The program for the third “Valley Vivaldi” concert on July 31 includes another movement from the “Musical Offering.”

Tickets: PASinfonia.org, 610 434-7811