Mobile phone operator Orange UK is trailing high-definition (HD) voice technology in Reading, Southampton and Bristol. The HD voice technology is expected to herald a new era for mobile communications by offering crystal clear and superior sound quality.

The new "Orange HD Voice" service will put an end to distorted calls, virtually eliminating the distance between the callers that will makes calls sound as if they are in the same room. But, the new service will not cost anything extra.

The HD voice technology will provide greatly enhanced sound quality with same network resources by using Wideband Adaptive Multi-Rate speech codec. A wider speed bandwidth of 50-700 Hz will be used in HD Voice calls to provide superior sound quality as compared with current narrowband speech code of 300- 3400 Hz.

Initially, HD Voice service will be available on a few of the 3G enabled handsets, but eventually it will be extended to a range of handsets compatible to offer HD Voice service. The operator said it believed that the new HD Voice service would be available nationwide by the end of summer.

Participants have been chosen to represent a range of demographic groups including early technology adopters and small businesses.