By now, you should have heard of Orkestar Zirkonium, the 14-member brass band with Central European style, known for musical sneak attacks on bars, grocery stores, and galleries, goosing innocent bystanders with their happy honking. Theirs is the sound of dizzy joy. Today, they play in Cal Anderson Park with jazz composer Paul Rucker, improviser Gust Burns, and noise-jazz band Non Grata. (Cal Anderson Park, 1635 11th Ave, monktail.com/soundsoutside.php. 3:30 pm, free.)