The Good: The Sennheiser Momentum headphones are an elegant full-size over-the-ear pair featuring a brushed stainless-steel headband and plush, leather-covered earpads. Sound and build quality are excellent, and the headphones come with a nice carrying case, as well as two cables, one of which has an Apple-friendly in-line remote and microphone. The Bad: The Momentum headphones are pricey and don't fold flat for compact storage. The Bottom Line: The Sennheiser Momentum headphones may not have enough bass to satisfy every taste, but they are in every other way the best-sounding full-size audiophile headphones we've heard in a long time. Sennheiser may have a wide-ranging lineup of headphones, but it's never offered anything like the Momentum before: a high-performance, audiophile-oriented headphone that's been specifically designed for use with phones and other portable music players.Not surprisingly, it's rather pricey at $350, but at least it looks like a sophisticated, premium item, with a leather-covered, brushed stainless-steel headband and nicely padded ear cushions. No, you won't mistake the Momentum for a mostly plastic or Ludacris model. It also doesn't sound like those trendy lines. Nowhere near as bass-heavy or pumped-up, the Momentum headphones sound crisp and clear with all types of music and movies. While they may not be perfect, they're easily among the best-sounding headphones in this price range.Design and features At first, the Momentum was only available in brown, but now it comes in a black version as well. Both have leather-covered earpads and a leather-covered headband. The metallic-finished earcups can be moved up and down on the slotted steel headband to conform to the listener's head shape and size. This is a closed-back design and offers moderate isolation from external noise.One potential downside for some buyers is that the Momentum model's headband isn't hinged, so the headphones won't fold flat. Then again, hinges are usually a weak point in headphone designs and are prone to breaking.When you put them on, the first thing you notice is that they're unusually light for full-size, over-the-ear headphones, weighing only 190 grams (6.7 ounces). Comfort is usually a Sennheiser strong suit, and at first, the headphones seemed very comfortable. But over longer listening sessions I found that the nicely cushioned earpads put more pressure against the tops of my ears than the bottoms and I was a little too aware of the thinly padded headband resting on my head. Of course, every head is different, so the Momentums may be perfectly comfy on your head, but I thought their comfort level was a tad disappointing.In terms of extras, you get two cables, a 52-inch one with an Apple-compatible three-button remote and microphone, and a 56-inch-long "plain" cable. The Apple cable has a hinged, all-metal plug at the end that connects to your phone, so it can be set to be vertical or up at a 90-degree angle. The in-line remote is also all-metal, which, combined with the all-metal plug, adds a luxury feel that can't be matched by the usual plastic construction of the competitors' cables.