Moving to HD voice

It's almost not fair to traditional telephone systems: in addition to the improved cost and features available with VoIP, it's now possible to get HD-quality audio, as well. If you've listened to a call over an HD link and compared it to standard telephone-quality conversations, you know that the difference is remarkable.

Traditional telephones squeeze the human voice and all other sound through a 4 KHz window--not very much room for a fairly tone-rich source. New HD audio codecs like G.722.1 and G.722.2 allow for much greater bandwidth to be devoted to carrying sounds. The result is greatly-improved quality.

HD audio doesn't just sound better: because more sound spectrum is carried in each conversation, those with certain types of hearing loss may find it much easier to carry on critical conversations in HD audio.

For more:
TMCNet.com has the complete article here.

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