Don't get me wrong, I don't think the ZP-S5 looks bad - it's finished in the same white and grey livery as every other bit of Sonos kit - but it's not going to be a highlight to your minimalist décor in the way that the Bowers & Wilkins Zeppelin is. To put this in perspective, my wife loves the way the Zeppelin looks, but thinks that the ZonePlayer S5 is ugly - I'm not sure I agree, but the fact remains that you can probably sneak a Zeppelin into your living room without argument, while a ZP-S5 might take some negotiation.
Face on, the ZP-S5 is dominated by a rectangular speaker grille, with a recessed white stand below it. Viewed from above, it takes on a trapezoid shape, showing that there's a reasonable amount of depth to the cabinet for housing the drivers.
Talking of drivers, you'll find no fewer than five inside the ZonePlayer S5 - you get two tweeters for high frequencies, two mid-range drivers and a single subwoofer to ensure that bass response is well taken care of. Each driver is powered by its own digital amplifier, while crossover duties are also kept in the digital domain thanks to Sonos' custom DSP technology. Presumably Sonos has included its active crossover DSP circuitry in the S5's DAC, making it the final stage of digital processing before the signal becomes analogue audio.
The results are very impressive, more so than I had expected in fact. Compared to almost any all-in-one speaker system or iPod dock, the ZonePlayer S5 is a cut above. Whether you're comparing to any number of iPod docks, or multi-room systems like Philips' Stremium, Sony's GigaJuke or Logitech's speaker equipped SqueezeBox products, the ZP-S5 sounds, simply better. However, Sonos still can't match the truly incredible sound quality produced by the Bowers and Wilkins Zeppelin, but then B&W is primarily a speaker manufacturer, so that's hardly surprising.
There's no doubt that the ZonePlayer S5 will convincingly fill a room - I found that I could happily listen to the music in the next room without pushing the volume past halfway. There's a surprising amount of bass, but it doesn't make the sound muddy as a result, and thankfully doesn't distort when the volume is pushed high. The bass is never overpowering either, no doubt thanks to the quartet of high and mid-range drivers, leaving you with a good degree of clarity.