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Home News VoIP HD voice is coming!
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HD voice is coming!

After over 100 years of telephony, this is the first revolution in voice quality in terms of extended bandwidth!

Telephony has always been limited to about 3.4 kHz bandwidth. Improvements have been made to eliminate background noises, amplify weak signals and avoid uneven attenuation of the upper frequencies. But the 3.4 kHz limit was and is always present, even in the latest digital PSTN technology.

Skype was the first major service provider to provide wide band HiFi like (HD or High Definition) voice quality with their advanced proprietary voice codecs. But this is kind of closed user group, not available for most users in their normal daily telecommunication. HD will not become available for standard POTS phones. Codecs and switches are fixed to use G.711 codecs with limited BW.

Already for some time there are improved codecs available which support more audio bandwidth (up to 7kHz, e.g. double of what we have today) while not consuming more transmission bandwidth. Those codecs consume more processing power for encoding and decoding, but processing power is not a big issue anymore.

G.722 is a wide band codec mainly used for fixed wide band VoIP. It exists already for a long time and has not so high processing requirements. G.722 is license free. On the other hand it consumes still 64kbps BW. Many soft clients and VoIP desktop phones support G.722.

AMR-WB is a more efficient codec specified by 3GPP for mobile communications. It consumes only 12.65 kbps for almost the same quality as G.722. It requires more processing power and the algorithm needs to be licensed. AMR-WB can be found almost exclusively on mobile phones.

AMR-WB is available, some phones support it already, but network operators were very hesitant to support this new codec. The network needs to recognize the codec and open a transcoder free (TrFO) or tandem free (TFO) transparent connection end to end.

First operators are now deploying HD voice using AMR-WB. This looks very promising and I think once subscribers get to try this high quality audio, they will never want to miss it! Competition has to catch up fast and we can expect that HD voice will now come faster to us!

See the convincing stories below:

Orange UK HD voice trial

Orange Armenia HD voice launch