Sprint unveils HD voice for cell phones

For all the amazing things smartphones can do, they're still not great at actual phone calls. Sprint's hoping to change that. The wireless carrier is rolling out new "HD Voice" technology to improve the quality of grainy cell-phone calls.

It's already available in a handful of cities, and should go nationwide by "mid-year," Sprint said.

Most people can hear within a range of ten octaves, but current cell phone calls span only four. That's why taking a call from an iPhone owner can sound like listening to someone through a set of tin cans.

High definition Voice expands a cell phone call's range to seven octaves. It also includes technology to eliminate background noise, giving voice calls a fuller, more natural sound. For the technology to work, both callers need to be Sprint customers using HD Voice-enabled phones.