Digital convergence is a phrase that continues to be thrown around computer circles, and products such as the Sonos Digital Music System aptly demonstrate the thinking behind it.

In short, it's an audio streaming device that you connect to a hi-fi (or a pair of standalone speakers) and play digital music stored on your computer's hard disk via a wired or wireless network.

You may already be familiar with similar gadgets from Apple, Netgear, Pinnacle and Creative. However, the Sonos is the 'Rolex' of its genre and, like the flash timepiece, it comes at a wallet-busting price.

At £668 for the most basic package, it's unlikely to be a justifiable expense for most, especially when some other products will do almost the same thing at a fraction of the price. However, the extra features make the Sonos the best audio streaming device we've ever seen.

It comes in two main parts. The ZonePlayer is a bread-bin-sized amplifier that has audio sockets on the back for connecting to a hi-fi or a pair of speakers. Its most important feature, though, is the integrated Wi-Fi that allows it to talk to your computer without wires.

There's a network port on the back if you prefer to use cabling, but Sonos is primarily designed to be a wireless music player that you can position anywhere in the house. What's better, you plug it in and it works. Literally.

The second component is the Sonos Controller, which is used to navigate through your digital music collection. And it's this element that really sets it apart from anything else we've seen of its type.

On the Controller is a 3.5in LCD screen which displays the name of the track playing, the artist, the album it's from, the next track scheduled to play and even album art.

The large iPod-esque touch pad is used to scroll through music and various other buttons allow you to pause, fast-forward and rewind tracks, adjust volume and manage playlists.

Not only is sound quality excellent, but there's no annoying pause between tracks and you can independently control up to 32 individual ZonePlayers with one remote control. We tried it with two and it worked great.

We're sceptical of Sonos' claim to 32 simultaneous players though, and think this would only be possible on a completely wired network.

It supports all popular music file formats MP3, WMA, AAC, Ogg Vorbis, WAV, AIFF and Flac music files and can be upgraded to support future audio formats. DRM-encrypted or WMA Lossless formats won't work though.

It will connect to internet radio stations and will also encode audio on-the-fly and broadcast it around the house through its line-in socket.

A couple of annoyances are the Controller's inability to scroll through long tracks, album or artists' name, and the fact that one ZonePlayer has to be connected to your router at all times.

Sonos is offering a bundle of two Zone Players and one Sonos Controller for £899. It is expensive, but you won't find a better example of a music streaming device on the market right now.

Also consider:
Creative Sound Blaster Creative Wireless