That's a shame, because apt-X makes a tangible difference to the quality of the ZiiSound D5's output, as was demonstrated when we used an iPod touch to switch between its built-in Bluetooth and the bundled dongle. Sub-band encoding, the fall-back alternative where apt-X is unavailable, just doesn't cut it in comparison.
Importantly, the ZiiSound D5 produces a high quality enough output to warrant the improved input. There's a surprising amount of bass for such a small system and it doesn't overwhelm the overall balance, instead adding a pleasing level of depth and warmth.
There's also great mid-range clarity, with vocals coming across particularly well. This is rounded off nicely with a crisp high-end too. Furthermore, the ZiiSound D5 produces a surprisingly wide soundstage for such a compact system, with defined stereo separation, as long as you don’t get too close.
It's no exaggeration to say the ZiiSound D5 can get pretty darned loud. The device had no problem spreading its audio throughout our office so unless you live in a particularly sizeable mansion you'll get room-filling sound in a home environment. Importantly, there was no significant deterioration in quality when cranking the volume up.
We'd probably still give the sonic advantage to the similarly-priced B&W Zeppelin Mini, but it's a close run. Where the ZiiSound D5 wins out is its versatility and, verging onto the subjective, its looks.
Creative isn't targeting the budget-constrained with the ZiiSound D5 - its £279.99 price tag makes that clear. It's not hard to see what that money is buying though. The ZiiSound D5's Bluetooth connectivity is well-implemented and it both looks and sounds great.