Sony is betting on its newly launched Walkman phone to crack the worldwide domination of Apple's iconic iPod.

The electronics giant has claimed a limited victory after beating Apple into second place as the top seller of memory-type music players for May and June, but only in the Japanese market.

In the UK Orange has announced that it will be the first to sell Sony Ericsson's new Walkman phone, the W800i, with a high-profile launch at midnight on 12 August in London's Oxford Street.

The orange coloured handset will be available free to Orange customers on selected service plans and will be configured for all Orange services.

But a study of digital music devices by TechnoMetrica Market Intelligence has found that 140 million adult Americans have not heard of the Walkman phone.

"Sony has still not got the word out about its Walkman phone," said Constantine Kambanis, an analyst at TechnoMetrica.

"Our findings suggest that the Walkman phone is poorly positioned for a head-to-head match against Apple's iPod or Dell's Digital Jukebox. It has a weak showing among the consumer groups that propelled the iPod to superstardom."

According to the report, typical iPod buyers are young people with a college education and relatively high household incomes.

And, worryingly for Sony, Apple appears to have greater momentum. The research estimated that 32 million adult Americans are planning to buy an iPod within the next 12 months.

Sony will also be hoping for better product reviews: an article on gadget blog Gizmodo is unlikely to motivate new buyers.

"Sony Ericsson continues to make nice looking phones that I have no desire to own. The Walkman is nice enough looking, but the music application didn't seem very advanced at all," said the blog entry.

"I'm happy to give it another shot in the future, but I was hoping to get something that seemed more advanced than the average media player application you can find on almost any modern phone."