Bolcom's curtain raiser, Circus Overture, was written in honor of Leonard Slatkin's 70th birthday and premiered by the conductor and the Boston Symphony, which commissioned it. It's a 5-minute riot, full of marching evocations of the midway - or perhaps the parade of life? - along with lickety-split wind lines, exaggerated tempo changes and a snippet of Ellingtonian talking brass, including a muted trombone growling out a reference to Chopin'sFuneral March.That's vintage Bolcom wit. Slatkin, who has championed the Ann Arbor composer for decades, specifically asked him not to quoteHappy Birthday. The Detroit Free Press, Oct. 10, 2014. Subtitled Into the Eighth Decade, versions for both orchestra and band are available for rent.