There's a good chance you own something that has a Cirrus Logic-designed audio chip embedded in it. As a major supplier to Apple, the company has been on a roll for a while, recording 27%, 67% and 15% respective revenue growth in the past three fiscal years, which Cirrus attributes to increased sales of portable audio products. Cirrus shares have more than doubled in value over the past 12 months, touching prices not seen since 2002. The Austin, Texas-based concern also makes integrated circuits for the energy industry, although that revenue line took a 27% hit in fiscal 2012. Growth at Cirrus now looks to be firmly tied to Apple and its audio chips. -- N.S.