The MP3 player market is saturated. It has been for years now, with every size, price point and storage benchmark catered for amply. However, when it comes to sound quality, it's hard to find a player that really stands up to be counted.

Some MP3 players have exasperatingly poor sound quality. And because they all come with shockingly cheap earphones, it's easy for people to not even notice - the manufacturers get away with it.

It makes sense then that Creative would be in a good position to fill this one area of the market that hasn't been given too much attention. The X-Fi technology it puts in its PC soundcard products is an ideal solution to these sound quality issues. And why not bung in some high-grade earphones to seal the deal?

The Creative Zen X-Fi is essentially the same size as Creative's last flagship MP3 player, the Creative ZEN. The semi-clunky interface is also pretty much identical. But there the similarities end.

Because while the Creative ZEN was a solid performer, it lacked a distinguishing feature. The Zen X-Fi, on the other hand, has four secret weapons.

Four Zen X-Fi weapons

The first is the aforementioned X-Fi audio processor, for superior sound quality. The second is a startlingly good Wireless LAN Wi-Fi function which allows you to wirelessly stream and download music from a web server, a PC on your home network as well as to and from other Zen X-Fi players.

The third is an internal speaker which makes the one on the Apple iPhone sound fairly pedestrian. And finally, the fourth is a pair of high-quality Creative Zen earphones which come as standard.

So, is the Zen X-Fi a hit or is it a miss?

Let's start the analysis with the X-Fi audio enhancement. The X-Fi menu in the interface give you two different options to choose from, X-Fi Crystalizer and X-Fi Expand. The X-Fi Crystalizer uses a special audio processing chip to restore the parts of music which gets mauled when a lossless track is compressed into an MP3 or WMA file.

Compression makes cymbals sound muffled and bass sound flat. X-Fi changes that by upmixing those parts of the music to artificially restore audio fidelity.

The X-Fi Expand option, on the other hand, aims to widen the soundstage of a song, so that instead of listening to a flat audio file, it sounds more like the band are playing live right in front of you.

In the right conditions, both of these technologies work brilliantly - but whether they are implemented well on this portable player is another matter. And rather predictably, the results were a bit hit and miss.

The X-Fi Crystalizer does improve sound quality - MP3's do sound much better when you switch that feature on.

However, the same cannot be said for X-Fi Expand. When you turn on the Expand setting, it makes the music sound rather flat and lifeless - the exact opposite of what is supposed to happen.

Still though, that's not too much of a big deal - it's the crystallization which makes X-Fi so good. And on that score, we're more okay. This is the best-sounding Creative MP3 player ever.

So how about the Wi-Fi function?

Surprisingly, the wireless features really do work fantastically well. If you add all your music to Windows Media Player on your PC, you can then make it accessible via your network. Which means you can play (and even download) music from your PC, to your MP3 player without having to plug it in via USB (you can do that too if you prefer).

It's great for those times in the summer when you're sitting out in the garden and you want to listen to a track you've not yet added to your player's own memory.

The only catch is that battery life suffers astronomically for every second you leave the wireless switched on. If you stream music with X-Fi switched on, get ready for your battery to die quicker than a kitten in a bucket full of water.

Next we come to the internal speaker. Have you ever wanted a friend to hear the song you're listening to without having to make them use one of your grubby earphones? With the Zen X-Fi, if you unplug your headphones, it'll switch straight to the external speaker so you and those around you will be able to hear the song you're playing.

It goes surprisingly loud, without a hint of distortion. A really great little feature, albeit with the potential to irritate those people travelling on the same bus as you.

And finally we come to the earphones. The sets you usually get with MP3 players (including all previous Zen's, all SanDisk Sansas and all iPods) are universally, unequivocally, undeniably awful.

Not so with this player. The bundled noise isolating earphones certainly are no match for an £80 pair of Shure earphones. But still, they're light-years better than anything we've seen come bundled with an MP3 player before.

So far then, this review has been overwhelmingly positive. And it's actually hard to find something to complain about.

The only real problem we have is the interface, which is a bit fiddly. The buttons on the front are rather cumbersome and the on/off/hold switch is curiously hidden away on the back which is surprisingly inconvenient.

But really, this is a great MP3 player. It's very light, and it's even got an SD card expansion slot which enables you to boost the 16GB of internal memory (also available in 8GB and 32GB - the 8GB version does not have Wi-Fi built in).

Finally we have a good MP3 player which holds sound quality as the most important feature. Something we've been waiting on for years. And even after the long wait, it's certainly no disappointment.