The concerto. It's a musical recipe more than 400 years old but composers still cook with it. And why shouldn't they? We still seem to crave the sound of a virtuosic soloist playing with (and often against) an orchestra. As in centuries past, virtuosos still inspire, and in many cases commission, composers to write some of their best music, which can push an instrument to its creative limit. We've come a long way since the earliest concertos by Torelli and Vivaldi, but some of the old formulas — from the three-movement template to the fast-slow-fast tempo indications — still ring through in contemporary concertos, including these three fascinating examples from John Adams, Japanese composer Toshio Hosokawa and Armenian composer Tigran Mansurian.