International Contemporary Ensemble

Mostly Mozart Festival. Is it a bigger surprise to find the intrepid new-music group known as ICE playing a starring role in a festival named after Amadeus, or to find the band playing a program chock-full of Beethoven? Either way, good luck tracking down a ticket for tonight's show, which includes accordion genius William Schimmel's solo arrangement of Beethoven's overture to Egmont, prefacing the same composer's String Trio in G and two works by German modernist Matthias Pintscher.