HD Voice is an audio codec, that gives you crystal clear, high definition voice calling, without background noise. It’s like talking to someone in the same room, even if the Vodafone Warriors have just scored.
You won't need to switch HD Voice on. If your phone supports HD Voice, it's enabled by default.
Vodafone launched HD Voice in February, 2013, to work with 3G calling. That means the phone you use today is probably HD Voice capable.
For HD Voice to work, you and the person you're calling both need to have an HD Voice compatible handset, and be on the Vodafone NZ network.
HD Voice is also known as Wideband audio.
While technically different, Voice over LTE (VoLTE) also provides crystal clear calling, delivered over 4G. VoLTE might also be referred to as '4G HD' or '4G Calling'. VoLTE needs to be enabled in the settings on your phone.