The PC 333D is a stereo headset with standard 3.5mm jacks at the end of its 2-metre cables, but it comes with an inline USB sound card that can be fitted if you need it. It's useful if you don't already have a decent internal sound card, or game on a laptop, because the USB adaptor mixes in 7.1 surround effects and has a switch for activating Dolby Headphone support.
We'd hope, however, that anyone spending this much on a headset has looked at the ASUS Xonar DG with its on-board headphone amp and support for Creative's EAX. Turning on the Dolby booster here simply seemed to add an unacceptable amount of reverb in most games. Instead of giving environmental effects depth, it just makes them sound like you're in a tunnel.
As a straight stereo headset, though, the sound quality lives up to the price. There's a carefully balanced tone that puts just the right amount of emphasis across the whole range. Bass tones are rich and chunky, but never overwhelming, while in the mid- to high-end voices aren't drowned out by background explosions.
They aren't just tuned well for games either. In favourite arias or clanging folk rock, guitars and vocals have a powerful edge, but you'll still be able to pinpoint the triangle player in the background.
For all that, though, the PC 333Ds are going back in their box and we'll be sticking with Sennheiser's older models (until we've had chance to review the PC 360s, at least).
The acoustic engineering that packs such a powerful sound into so compact a headset is admirable, but the PC 333D isn't comfortable enough to wear on a man-sized head for long gaming sessions. The clamp pinches the skull and the small earcuffs sit almost painfully on the pinnae.
If we had this amount of money to spend on a headset, we'd go for something more comfortable, such as the Logitech G35s or Steelseries 7H. Or just stick with the PC 350s we already have, of course.
The Sennheiser PC 333D is capable of exceptionally good sound quality considering the size, and comes with a useful, but far from essential, USB sound card. The silver flashes on the sides are from the cheesier end of the design spectrum, but although its lightweight, it feels well built, too.
The small ear cuffs just didn't sit well on our jug-eared skulls, and at this price we'd want over-the-ear noise reduction too. Definitely a case of try before you buy, or long gaming sessions will leave you sore.
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