Beethoven’s Ninth is big; Verdi’s Requiem is bigger. But the biggest show in classical music is Mahler’s Eighth Symphony. The “Symphony of a Thousand” requires an enormous orchestra, an off-stage brass band, eight vocal soloists, a children’s choir, and a gargantuan adult choir. And now the UMS Choral Union–the only chorus between Chicago and Cleveland capable of singing it–has been approached by three different orchestras about performing the Eighth in 2011.

Choral Union leaders won’t identify the contenders, but sources say the Ann Arbor and Detroit symphonies are in the running, while officials at the Flint and Toledo symphonies confirm they’re out. Who’s the third? Possibilities include a visiting orchestra, the U-M University Symphony, and the Grand Rapids Symphony–the Choral Union did Mahler’s Eighth with it ten years ago. The UMS says it will announce its choice by the end of the year.