Having debuted Christopher Theofanidis' "Creation/Creator" just last week, the Atlanta Symphony Orchestra is preparing for another world premiere by a different member of its Atlanta School of Composers. Michael Gandolfi's "Imaginary Numbers," a concerto for four soloists and orchestra, will be performed in concerts at 8 p.m. Thursday and 7:30 p.m. Saturday.

Jean-Yves Thibaudet returns to Symphony Hall to perform Ravel’s Piano Concerto. Music director Robert Spano will lead the ASO in Stravinsky’s "The Firebird Suite" and Gershwin’s "An American in Paris."

At 6:30 p.m. Friday, the maestro conducts an abbreviated version of the subscription concert (featuring the Stravinsky, Ravel and Gershwin). The “First Friday” concert is intended to introduce Midtown office workers and others to the ASO at a reduced admission (all seats $25).

The premiere by Gandolfi, chair of the New England Conservatory of Music's Composition Department, was commissioned by Paul and Linnea Bert in honor of their long-time friendship with Dede and Tony Spano and their son, the ASO music director.

ASO principals Elizabeth Koch Tiscione (oboe), Laura Ardan (clarinet), Keith Buncke (bassoon) and Brice Andrus (horn) will be featured.

Read Gandolfi's notes about "Imaginary Numbers" here.

$25-$104. 1280 Peachtree St. N.E., Atlanta. aso.org.

Atlanta Symphony Orchestra Assistant Conductor Joseph Young.

Credit: hpousner

icon to expand image

Credit: hpousner

Young to conduct Atlanta Music Project Orchestra

Atlanta Symphony Orchestra Assistant Conductor Joseph Young will guest conduct the Atlanta Music Project Orchestra’s 2015 Spring Concert at noon Saturday in the Woodruff Arts Center's Rich Theatre. The concert will feature the 50 young artists of the Atlanta Music Project’s Gilbert House-South Bend Orchestra. Young will lead the group in works by Offenbach, Holst, Handel and Mozart.

Free. 1280 Peachtree St., Atlanta www.atlantamusicproject.org.

Singers from Just Voices, which will be in concert May 2 and 3. CONTRIBUTED BY PETER POLITES

Credit: hpousner

icon to expand image

Credit: hpousner

Just Voices take time for theme

The spring program the Atlanta a cappella choir Just Voices’ will present on May 2 and 3, “It’s About Time,” will include one work that took some 500 years to complete.

Renaissance poet Garcilaso de la Vega (1503-1536) wrote a poem of love that he simply titled "Soneto V." Fast forward to the 21st century, and conductor-composer Z. Randall Stroope, now director of choral and vocal studies at Oklahoma State University, finally set the poem to music, titling it "Amor de Mi Alma" ("You Are the Love of My Soul").

Like “Amor” or the Irish traditional tune “Quick! We Have But a Second,” the pieces to be sung by the 24-singer group under founding conductor Liz Frazer address time’s passage in one way or another.

Including classical music, spirituals, folk and jazz, the concerts will be at 7:30 p.m. Saturday, May 2,5/2 at Virginia-Highland Church, 743 Virginia Ave., Atlanta; and 4 p.m. Sunday, May 3 at Holy Trinity Parish, 515 E. Ponce de Leon Ave., Decatur. Tickets: $10 door, $5 students. www.justvoices.org.