NEW MARLBOROUGH -- Johann Sebastian Bach knew what to do with a musical riddle.
A concert at the Music & More festival at the Meeting House on the Village Green in New Marlborough will revisit a historic encounter in which the great Baroque-era composer presented his response to a royal challenge.
Daniel Stepner, Baroque violinist and artistic director of the Aston Magna Music Festival, which enjoyed its 40th anniversary season this summer, will lead a quintet of musicians (drawn from the ranks of Aston Magna) through a program of music highlighting Bach's rich and mysterious "Musical Offering," as well as a violin sonata by his son, Carl Philipp Emmanuel Bach, and a sonata by Frederick the Great, onetime king of Prussia. The concert is Saturday at 4:30 p.m. A talk on the music precedes the concert, at 3:30 p.m.
"In a kind of piece like ‘Musical Offering,' you have a sense of getting inside of Bach's mind, kind of a mathematical musical genius. With any great Bach piece you have the sense of being inside the mind of a true genius," Stepner said in a telephone interview.
Joining Stepner are Christopher Krueger (Baroque flute), Jane Starkman (Baroque violin and viola), Laura Jeppesen (viola da gamba) and John Gibbons on harpsichord.
The group is well-familiar with "Musical Offering," having played it on tour and making a studio recording of it, but this will only be the its second time playing this full, thematically constructed program.
The piece arose when Frederick the Great sent the elder Bach a musical theme and challenged him to write a fugue for three voices based on it. (A fugue is a composition in which a theme is repeated by two or more instruments, repeatedly and in counterpoint.) Bach did, but then Frederick upped the ante, challenging him to write one for six voices.
The great composer arrived at court, where his son was the court harpsichordist, with a series of compositions including the six-voice fugue, 10 canons and a sonata for flute, an instrument Frederick played.
Saturday's concert evokes the 1747 musical summit among Bach, his son, and the monarch.
The concert will be Stepner's second visit to the late-summer festival, which has just begun its 21st season. His appearance last year, leading a trio performance of Bach's "Goldberg Variations," greatly impressed Music & More director Harold Lewin.
"It was really an eye-opener," said Lewin, an experienced concert pianist who had not made a practice of including Baroque music in his festival. "The voicing became so crystal clear, it was a revelation. It was fascinating."
This will be the first concert at Music & More to include a harpsichord, Lewin said.
"Musical Offering" stands out among Bach's work, Stepner said, for a few reasons. Though his compositional hand dictates the proceedings, there is an unusual amount of room for interpretation by the musicians who play it.
There are no surviving notes stipulating a specific order in which the 13 pieces should be played. Several of the pieces do not stipulate which instruments should be included. And in the canons (sometimes nicknamed the "riddle canons"), in which different instruments begin working their way through a melody at different times, there are no fixed points where each player should begin.
"Bach wrote one line and challenged the players to find out where the second voice comes in," Stepner explained. "He challenged the players to come up with different points of entry so the canons work."
Adding a bit of historical context to the "Musical Offering," the program also brings in Carl Philipp Emmanuel Bach's trio sonata in C minor, with two parts subtitled by the mood each is meant to invoke: "sanguineus" and "melancholicus."
"They interact with each other and they try to persuade each other to come to the other side, so to speak. Eventuality the cheerful one wins out," Stepner said.
The king whose challenge prompted Bach's great work is represented with his Concerto No. #3 in C major for flute and strings.
In this combination of works by three composers, listeners will get a little taste of music at court in the 18th century, on an occasion that revealed the enigmatic genius of one of Western music's greatest composers.
"I was excited about getting these wonderful musician to play this really fabulous music," Lewin said. "The ‘Musical Offering' is an incredible piece. It's very complex and interesting music, just the way it's put together."
What: Music & More, Bach's ‘Musical Offering'
Where: Meeting House on the Village Green, 154 New Marlborough Road, Route 57, New Marlborough
When: Saturday, talk 3:30 p.m., concert at 4:30 p.m.
Information: (413) 229-2785, www.newmarlborough.org