It may look like yet another mid- priced AV receiver, but behind the RX-N600Ds familiar titanium coloured fascia is a story of AV-IT convergence. Okay, the USB port on the front is a bit of a giveaway - this is Yamaha's first Network AV receiver.

Using Windows Media Connect it allows you to play MP3, WAV and WMA music files from a remote PC, or listen to any radio stations on the internet. If you have a Yamaha MusiCAST system, the N600D acts as a seamless client and plays music files straight off USB storage devices. If that's not enough ways to feed digital music into your home entertainment system, it has a dedicated port for the Yamaha YDS-10 iPod dock, and a built-in DAB tuner.

The flip-side of cramming in all this in for under £600 is that many of the AV features that competitors sport at this price point have been axed. There's no HDMI switching, auto- setup or RoomEQ functionality and it's 6.1 channel rather than 7.1, so you can only use a single centre rear- surround speaker. The standard AV connections are all present, albeit in fairly limited numbers and surprisingly basic.

This means the AV setup is very swift of course, but the same can't be said of the networking. In true PC- networking style, nothing worked first time or without convoluted faffing. The idea is that you download Windows Media Connect to your host PC, click on file sharing, connect your Ethernet cable, update your internet radio lists from the vTuner database and away you go, with the N600D displaying station names, and full folder and track list information from your host PC's music catalogue or USB drive... theoretically.

After three hours of messing around with DHCP settings, MAC addresses, changing cables, re-installing WMC and reconfiguring Firewalls just to get device list on my PC to recognise the N600D, it was finally set up. So, ease of networking setup, nil points... but that goes without saying when PC technology is involved.

Action stations

If you're familiar with the sonic glory of CDs, Dolby Digital, DTS, DTS 96/24, etc, on your AV system, then listening to 128kbps MP3 or WMA files through a potent AV amp and speakers is a horrific experience. The dynamic capabilities of the system highlight the limited sound quality of these data-reduced file formats, and make them sound worse than through personal devices. So treat this feature as a utilitarian background noise-generator.

Thankfully, the N600D is saved from a serious drubbing by decent core surround sound-processing and a robust sound reminiscent of much beefier amps.

Actual power drops considerably when the receiver is in multichannel mode, but surround sound is weighty and solid, with real low-frequency presence in the room. Big action sequences can impress despite relatively humble power figures, and hooked up to a traditional speaker package, the N600D really bullies the room.

For Dolby Digital and DTS soundtracks, the N600D lacks the sparkle and power of the best at this price point, and this keeps the soundstage compressed. It never really gets out of the box, or creates that marvellous illusion of turning your living room into a massive cinema.

On the flip-side, this darker balance does wonders for smoothing the DAB radio and internet radio sound, both of which can have a tendency to be a bit bright on lower bit-rate broadcasts. The same is true to an extent of the MP3 playback, which is fair, all things considered. Don't go near the Compressed Music Enhancer feature, however, as it has all the subtlety of a 'loudness' button on a cheap hi-fi.

By trial and error rather than any salient information in the Yamaha manual, I discovered the N600D decoded WMA Variable Bit Rate format even on the highest setting, 240-355kbps, although sadly not WMA lossless. VBR makes a spectacular difference in sound quality compared to vanilla 128kbps files, though there's an inevitable impact on hard disc space.

Despite venting my spleen about MP3 in an AV scenario, there is a certain appeal about having all your music available without a trip to the CD shelf. Okay, I had some issues with setup on the network side, but once WMC is running smoothly on the host and you sort out Yamaha's quirky remote control, it is actually very simple and convenient to access all your stored music... which is pretty much the point, of course.

The N600D is undoubtedly a clever bit of kit, and points the way towards the convergence of AV and IT that pundits have been predicting for many years.

The issue is that the network technology side of this receiver is not simply an add-on - it has ousted lots of really important AV features, particularly HDMI and the seventh channel. But then, it's clear that Yamaha is trying hard to reach an entirely new audience for big-box receivers. If the brand can reach this iPod/PC crowd, the rewards could be huge - but traditional AV fans might well feel disenfranchised.

As a home cinema enthusiast, I have my reservations about the N600D. Put it this way; would you spend £600 on an AV amp to play MP3s from your PC... or on one which would make the most of home cinema surround sound and the HD video revolution? Richard Stevenson