A technology that improves voice clarity on mobile phones by filtering out unwanted sounds is on offer.

High Definition (HD) Voice claims to reduce the background noise and 'hisses' that often mar mobile phone calls and offer users 'crystal clear' sound.

HD Voice, which went live Wednesday, should help those people who frequently make calls from trains and noisy workplaces, reports the Daily Mail.

The firm also claims that HD voice is able to 'eliminate the perceived distance between callers making it easier to hear the emotions in people's voices.'

Jonathan Leggett of mobile phone comparison website Top10.com said: 'It's ironic that as smartphones have become more multi-functional, they're arguably not much better at their primary function as a conduit for calls.

'We don't expect Orange's HD Voice technology to sway young smartphone users.

'However, improving the calling experience will appeal to less tech-hungry consumers who use their handsets predominantly for making calls and texting,' added Leggett.

Recent research from Orange has shown that a third of business leaders say they routinely struggle to hold phone conversations due to the noisy environment they work in.

Other countries already have networks using the technology including Moldova and Germany.