Orange is making its High Definition voice service available across the country from today.

The mobile network announced the service, which uses a speech bandwidth of 50-7000Hz compared to the current narrowband speech codec of 300-3400 Hz, in January this year.

It was followed by trials in Bristol, Reading and Southampton during June. Orange says the service will eliminate separate background noise and conversations to ensure voices can be heard more clearly and will be ideal for making calls in noisy areas such as parties and concerts.

Currently, the service can only be used with the Nokia 5230, Nokia X6, Nokia E5 and Samsung Omnia Pro, as they already feature the technology required to handle HD calling. However, Sony Ericsson and Nokia are working on additional compatible handsets.

Tom Alexander, chief executive of Everything Everywhere, the parent company of the mobile network created when Orange merged with T-Mobile earlier this year, said: "Although what we use our mobile handsets for has evolved significantly in the past few years, the way we make mobile calls hasn't changed a great deal since the 1990s. We're offering customers a revolutionary new calling experience."

"With mobile HD Voice - hearing really is believing."

See also: Orange leads HD mobile voice race