HD Voice uses the Wideband Adaptive Multi-Rate speech codec, using bandwidth between 50 Hz and 7000 Hz compared to the current narrowband speech codec which uses 300 Hz to 3400 Hz.
Some have argued that consumers have taken to VoIP services, despite some occasional quality issues, because they had been so widely accustomed to mobile voice audio quality, objectively and not only subjectively worse than landline quality. The Orange enhancement at least potentially could have positive impact, but in the opposite direction, making mobile voice audio quality objectively and subjectively better than either legacy mobile voice or landline voice using the public switched network.
“HD Voice really does inject a level of innovation into mobile phone calls, making it sound as if callers are actually in the same room,' Tom Alexander, Orange UK CEO, said. 'Once people have tried it, they won’t want to go back.”
