The portable speaker market has become a saturated place, which has led to many manufacturers trying to differentiate their products in a number of ways.

The Yamaha NX-U10's niche is the first USB-powered speaker to offer 20W of sound as opposed to the standard 0.5W.

It comes with a USB lead, a power adapter and a portable battery pack. The USB port is hidden away in a corner underneath the battery flap and not instantly visible. The lead itself could also have been longer.

However, we have no complaints about the sound, which is very impressive for its size. When connected to an iPod the sound was exceptionally clear and fully balanced. Even at full volume, there was only a slight distortion. We found it loud enough to fill a large room and the bass, which has been blessed with Yamaha’s SR-Bass technology, could be heard next door. Great for parties, bad for neighbour relations.

Testing the NX-U10's through a notebook computer and USB connection, the sound got slightly tinny when turned right up, however, it was difficult to differentiate between this and a bigger computer speaker system.

We also tested the sound on a Sony PSP while watching a film from its memory stick. It wasn't as clear as we'd hoped but still immersive and makes watching a film on the move a realistic option. The battery pack also makes it a great travel accessory.

We liked the silver contemporary design and, because the speaker is small and light, it can also be placed next to a PC, on a small table, or made portable through a battery option. However, at £150, it's not cheap.

Also consider:
Intempo iDS-01
A decent attachment but rival devices offer battery-powered playback and other features

Saitek i-Phonic A-100
A good set of travel speakers

Minispeakers K8000
Outstanding sound quality from this compact speaker system

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