Laptop speakers are poor substitutes for external separates, so there is a growing market for small portable units, of which the Yamaha NX-U10 is the latest and most impressive.

With two 10-watt speakers, controlled by what Yamaha calls its 'Charged Capacitor Amplifier', the speakers are up to 10 times louder and clearer than standard speakers of this size. Equally, Yamaha's SR-Bass technology reproduces 'the deepest bass ever' in relation to the size of speaker.

You can choose whether to run it using four AAA batteries, or you can opt for external power via USB or mains power.

At £150 (inc. VAT), these are far from an everyday set of speakers, but the overall sound quality is better than anything we've heard before. You could even use them with any MP3 player.