T-Mobile USA Launches HD Voice

T-Mobile USA is the first carrier to launch HD voice service in the United States.

T-Mobile USA said HD Voice is now available on its network nationwide for customers with HD voice capable smartphones, such as the HTC One S, Nokia Astound and Samsung Galaxy S.  Both parties on the call must be using HD Voice capable smartphones and be connected to T-Mobile's HD Voice-enabled network. There is no additional cost. T-Mobile said users will experience fuller, more natural-sounding voice
quality with significantly reduced background noise.

T-Mobile HD Voice leverages the Wideband Adaptive Multi-Rate (Wideband AMR) codec – a technology which accommodates an audio frequency range that’s twice as wide as a regular, narrowband cell phone call – as well as enhancements to the microphones and speaker systems in T-Mobile smartphones.

“T-Mobile is enriching the customer experience on its network with our nationwide launch of HD Voice. In addition, multiple third-party tests have shown that the experience on T-Mobile’s nationwide 4G network rivals major competitors’ LTE networks,” said Neville Ray, chief technology officer, T-Mobile USA. “This year, we’re stepping on the gas again. We are making continued coverage improvements and launching an advanced LTE network that will reach 100 million people by mid-year and 200 million people by end of year.”

http://newsroom.t-mobile.com/press-kit/t-mobile-hd-voice