HD Voice (aka wideband audio) on cellular networks has been coming soon for several years, but on May 15 AT&T finally announced it rollout. So it is almost a year behind T-Mobile and Sprint (News - Alert) on this, though ahead of Verizon.
Like Sprint and T-Mobile, the codec AT&T is using is AMR-WB, which isn't particularly modern, but as long as they can all agree on one, it will eventually be better than what we have now. But users won't hear much difference in their calls for the foreseeable future.
First, AT&T (News - Alert) is only deploying it in four markets for now. Second it's only going to be available on some phones. Third, I doubt it's going to be gatewayed between carriers without transcoding down to G.711 or worse, G.729A, which will wash out all its benefits. Fourth, much of the lousy audio quality you are getting on your calls isn't because of the codec, it's from poor coverage or crowded cells.
It doesn't have to be this way.
Because they run over both Wi-Fi and the cellular data network, apps like Apple FaceTime (News - Alert) and Google Hangouts are less prone to coverage issues. Their audio codecs are vastly superior to AMR-WB both in terms of frequency response and robustness to poor network conditions, and they offer video as well as voice. So why don't the carriers just go with a similar solution?
Michael Stanford has been an entrepreneur and strategist in VoIP for more than a decade. (Visit his blog at www.wirevolution.com.)
Edited by Maurice Nagle