Making VoIP Calls in HD Voice
VoIP Call Quality
Most of the time, VoIP providers strive to achieve the same telephone quality as that enjoyed by the traditional PSTN experience. That is in fact, the holy Grail of VoIP – people must not know that they're using a completely different technology from the one they're used to. Not many people know however, that VoIP has a lot more potential than this. It is needlessly limiting for SIP providers to strive for mere parity with the regular telephone systems. Configured correctly, VoIP has the capability to deliver sound quality that is far superior to what we're used to.
When voice is sent over a network – whether the Internet or the traditional telephone wires – it has to be encoded into a form which can be easily transmitted. The type of encoding will determine the quality of the voice you hear at the other end. In order to save bandwidth, regular telephone conversations encode voice data at 8 kHz. This is sufficient for most needs but we still run into problems understanding the other person when asked to spell out something for example. P gets confused with B and even D. This is because the higher and lower frequencies are truncated. It's a system which has worked pretty well for us so far. But it hasn't changed in a long, long time.
VoIP promises to bring us conversations in HD voice which utilizes superior codecs and brings unprecedented clarity to telephone conversations.
Utilizing HD Voice
HD voice is difficult or impossible to achieve if one of the participants in a telephone conversation is using a traditional PSTN phone. This is because the POTS is the weak link in the chain and any signal has to drop down to it. It means that even if a VoIP system is capable of transmitting HD voice, the person at the other end will not reap the benefits unless the two are using the same codec. For this reason SIP to SIP calls are not only free, they can also take place in outstanding HD quality voice.
There are a number of codecs used to encode voice on the IP networks. Many of them are free to use, but some of them require a paid license. When two SIP providers negotiate with each other for transmitting a VoIP call, they have to agree on the specific codec to use. Creating SIP accounts with various providers will allow you to find out what codecs each supports. Different SIP clients will request various pieces of data for configuration with your VoIP SIP provider. Contact your ITSP to find out what are the optimal settings on SIP client for use with their network.