TMCnews Featured Article
April 19, 2012
The Technology Behind HD Voice
By Susan J. Campbell, TMCnet Contributing Editor
Is it possible for sound through telephony to be better than your ears have the ability to hear? This comparison was made to an individual’s vision when HDTV first emerged. Look how far this technology has come. With the widespread adoption of HD voice, communications are about to get a whole new sound.
This Multi-Channel blog describes HD voice exactly as I put it above – “better than your ears can hear”. It’s also referred to as demonstrating the difference between any airline’s complimentary earbuds and earphones from quality maker, Bose.
This high quality sound available in HD voice is possible through its use of a little bit of bandwidth paired with a little bit of codec. When the two are combined together, the result is better overall audio resolution.
Of course, referring to a “little bit” of anything is subjective. To be more specific, HD requires requires 7 kilohertz (kHZ), as compared with the 3 MHz or more necessary for one stream of HD video. To achieve HD voice quality, the little bit nearly doubles and a phone would use roughly 4 kHz per conversation.
When you look at the technology overall, any stretch into higher or lower frequencies ensures the human ear can pick up more. When moving from 4 kHz to 7 kHz, for instance, consonants will sound clearer. Likewise, dropping into the lower band – 300 Hz down to 50 Hz – will add depth and clarity to the call.
The fun thing about HD voice is that even if only one phone in the conversation has the HD codec, the call quality overall improves. To truly optimize on the HD voice, however, dual-codecs are ideal: one in both phones. When this happens, we should no longer have to ask the person on the other end of the call to repeat anything.
This high quality communication tool has already launched in Europe. In fact, it’s been there for six years. The Multi Channel writer is hoping to see HD voice launch throughout the states, and I’m right there with her. Talking to a friend on her older BlackBerry (News 
- Alert) while I am on my iPhone 4S, it was difficult to make out every word. In the age of the smartphone – that should even be an issue.
Given the importance of high quality communications for consumers and business professionals alike, the demand for HD voice is only expected to grow and those providers leveraging this technology first will enjoy the competitive advantage.
Edited by Stefania Viscusi
Internet Telephony Magazine
Click here to read latest issue
CUSTOMER 
Cloud Computing Magazine
Click here to read latest issue
M2M Evolution Magazine
Call Center/CRM
Info Tech 
IP Communications 
Mobile 
Green 
Satellite 
Robotics 
