Much of the buzz surrounding the iPhone 8 and iPhone 8 Plus has focused on the glass back, wireless charging, A11 Bionic processor and improved camera. Turns out Apple has more up its sleeve. The latest iPhones are the first to officially support EVS, the Enhanced Voice Services codec. The iPhone X will also launch with EVS on board, but what does it mean for iPhone calling?
EVS provides a wider frequency range than the previous standard in use, known as AMR-WB. This codec is used by many voice over LTE networks, however the maximum frequency is 7 KHz. EVS offers up to 14.4KHz, providing dramatically better sound reproduction. The upgrade has been described as offering noticeable, more lifelike voice calling compared to older technology.
Interestingly, Apple included EVS-capable Qualcomm modems in many iPhone 7 units. It seems Apple kept the feature under wraps, as some iPhone 7 copies were instead equipped with non-EVS Intel modems. Apple waited to deploy the codec until the iPhone 8 and iPhone 8 Plus, which include EVS support on all modems across the board.
Carriers are slowly adopting the new standard, which was certified by 3GPP last year. T-Mobile was the first US carrier to begin rolling out EVS on their LTE network. Look for additional service providers to continue the trend as more devices with EVS call quality become available.