Rice University Shepherd School of Music has unveiled its 2023-24 season. Here is a rundown of the vocal performances on offer. The season opens with “Harmonious Horizons,” which includes a performance of “Knoxville: Summer of 1915,” starring soprano Michelle Bradley. Robert Spano conducts the concert, which also includes Barber’s first symphony and Jennifer Higdon’s “Concerto for Orchestra.” Performance Date: Sept. 29 {…}