With few exceptions, smartphones have never really been seen as serious audio equipment because of compromises that must be made for the sake of portability, size, and price. Lately, however, there has been an undercurrent in both the mobile industry as well as the digital audio market that is turning heads, or rather ears. More than ever, greater attention is being paid to digital audio quality, even on smartphones, as terms like “hi-res audio” become mainstream. But what is hi-res audio really and how is it affecting even the mobile market? We take a deeper look, or rather a deeper listen.