HD Voice announced by AT&T for select markets; service will launch on May 23rd

May 23rd is a big day for some AT&T subscribers. A week from Friday, the carrier will flick the switch, turning on its HD Voice service. The enhanced audio feature will work over AT&T's VoLTE network. And those using the service will be able to surf the web and be engaged in a phone conversation at the same time.
The first device that will support HD Voice is the Samsung Galaxy S4 mini. HD Voice will be supported on other phones throughout the year. For AT&T customers to enjoy the benefits of HD Voice, both parties on a call must be using a phone that supports the feature, in a market where coverage is available. While there is no charge for HD Voice, customers must have their accounts enabled for the feature.
source: AT&T
The initial markets that AT&T will blanket with this service include select markets in Illinois, Indiana, Minnesota and Wisconsin. The nation's second largest mobile operator will expand VoLTE and HD Voice on a "market-by-market basis"
The first device that will support HD Voice is the Samsung Galaxy S4 mini. HD Voice will be supported on other phones throughout the year. For AT&T customers to enjoy the benefits of HD Voice, both parties on a call must be using a phone that supports the feature, in a market where coverage is available. While there is no charge for HD Voice, customers must have their accounts enabled for the feature.

source: AT&T
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