Compact cranks have a 110 mm Bolt Circle Diameter (BCD) and standard cranks have 130 mm. The smallest ring that can fit on a standard road crank is 38 teeth, and the smallest on a compact crank is 34 teeth. So, to go compact chainrings, you need a new crank.

A good compact crank like the SRAM RED will shift just as nicely as a good standard crank (probably as well as or better than the s-works, which will be a relabeled FSA or something), with the caveat that the front derailleur should be set up correctly. There are "compact specific" front derailleurs, but I never could tell the difference- normal derailleurs work just fine for me.