6.1. Audio bandwidth for speech (informative recommendation)

Where ICT provides two-way voice communication, in order to provide good audio quality, that ICT should be able to encode and decode two-way voice communication with a frequency range with an upper limit of at least 7 000 Hz.

Notes

1. For the purposes of interoperability, support of Recommendation ITU-T G.722 [i.21] is widely used.
2. Where codec negotiation is implemented, other standardized codecs such as Recommendation ITU-T G.722.2 [i.22] are sometimes used so as to avoid transcoding.

Testing methods

The tests in clause C.6.1 are made available to support the recommendations in clause 6.1. They should be applied if the recommendations in clause 6.1 are being followed. However, tests in clause C.6.1 do not form part of the compliance requirements and are not required in any compliance report.