The B15's quoted three-hour battery life seems reasonable, although we think in practice the device gives up after just 2.5hours. If the battery is flat and you need to recharge it via the wall socket (or in-car cigarette lighter charger), the battery needs to be removed.
Every bit the high-end Blu-ray player, the B15 produces pin-sharp pictures on its tiny LCD screen. The unusual resolution isn't a problem – there's more than enough detail on show from our Blu-ray test disc Valkyrie – while contrast is sufficient. Colours can seem a little too vivid, we did notice some fairly constant picture noise and the viewing angle is tight.
Aside from that, none of these problems are particularly disruptive, partly because the picture is so smooth. Added to which, there's a limit to how much detail the human eye can discern on such a small screen anyway. However, the B15 is eons ahead of any portable DVD player we've seen before. It also makes for a fabulous in-home Blu-ray deck.
Attached to a full HD 32in television via HDMI, the B15 offers up some of the smoothest pictures we've seen. For example, while an overhead camera captures von Stauffenburg and von Haeften escaping the Wolf 's Lair by car, the individual leaves of the forest canopy can be clearly seen.
Close-ups of the speeding car are also impressive, with little in the way of blurring. A scene from Berghof where von Stauffenburg meets Hitler contains plenty of colour, depth and detail, despite the gloom. Upscaled DVDs are also enjoyable, proving the worth of P4HD, while even DiVX files played from a CD-R are watchable.
Simple headphones are fed as detailed a sound as any portable DVD player is capable of. Lack of space rules out analogue audio outputs, but the B15 manages to squirt Dolby TrueHD and DTS-HD Master Audio soundtracks to a TV over HDMI with stunning results. Once again, it's every bit as advanced as most Blu-ray players.
We do have concerns about its speed and battery performance, but in all other areas the B15 makes for an excellent in-home Blu-ray deck, permanently set up in your living room, but promise it some weekends away as well.
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