Brian Nohe, a former executive at Gillette (PG) and a self-described garage band musician, was running a small company in Delray Beach, Fla., that made headphones and earbuds for kids when he got a call from 50 Cent. The rapper and businessman (also known as Curtis Jackson) hadâ€”like just about everyone elseâ€”noticed the success of Beats by Dr. Dre and had decided he wanted to get into the business. He ended up buying a majority stake of Noheâ€™s company in September, renamed it SMS Audio, and made himself chief executive. The company sells headphones for all ages now: Sync by 50 wireless headphones go for about $400 and the Street by 50 wired sets cost about $250. The company has 25 employees and sells headphones in 30 countries. Nohe spoke with me over the phone about what itâ€™s like when 50 is the boss.