Sony Altus MDR-D777LP
Sony's new Altus MDR-D777LP headphones are quite unique in their technical design: they're circumaural (around-the-ear) headphones that look as if they'd be closed/sealed -- meaning they physically block out external noise -- but they have a switch on each earpiece that lets you choose between closed and open modes. Unfortunately, this interesting feature doesn't offer much in terms of real-world performance differences.
Overall, the D777LP headphones are fairly small for "full-size" models: folded for travel, they're approximately 5.5 by 4.5 by 2.7 inches in size; each earpiece extends down for use. At only 6.5 ounces, the D777LP is also lightweight, despite the brushed-aluminum pieces that cover each plastic earpiece. The earpads and headband pad, which feel like real leather, are surprisingly soft and very comfortable.
However, the D777LP's small size has two drawbacks. The first is that if you've got a wide head, the headband is a bit tight. The second is that the earcups are quite small; those with larger ears will find the D777LP to be more supra-aural (on-the-ear) than circumaural (around-the-ear) -- a difference that affects sound quality, since the D777LP's earcups are designed to enclose your ears and sound best when you get a good "seal" around each. That said, if your head and ears are small enough to fit the D777LP well, you can listen for hours in comfort and the earpieces block an impressive degree of external sound.
Although Sony advertises the D777LP as a "high-end" product, and touts features such as "80kHz High Definition Driver Units" that sit parallel to the ear, the D777LP's sound quality can't compare with that of true higher-end headphones; in fact, the D777LP doesn't sound quite as good as a few other well-regarded headphones at this price point. On the other hand, it's better, in my opinion, than that of Bose's $140 TriPort (a.k.a. Around-Ear Headphones) -- which is the product you'll most likely see next to the $150 Altus MDR-D777LP in electronics chain stores. (The Bose headphones are a bit lighter and feature larger earcups, but don't block quite as much external noise.)
The D777LP's bass response is solid; it's not quite as tight as I would have liked, but it's not overly boosted or boomy, either. (The latter is a common issue with "consumer" headphones in this price range, so it's nice to see Sony avoid that problem here.) Midrange is emphasized a bit, which, together with treble detail that isn't quite as clear as you would expect given the "80kHz" boast, results in a forward sound that's missing a bit of top-end detail -- you don't get the clarity of better headphones. (For example, Sony's own MDR-7506 pro-studio headphones, which cost less, offer notably better detail, although at the expense of the D777LP's warmth.) Finally, the D777LP offers good stereo separation, with decent soundstage and imaging, but with a slightly "hollow" sound that's often a characteristic of closed headphones. (Though it's worth nothing that the D777LP's sound has less of this hollow sensation than that of the Bose headphones mentioned above.)
What about those closed/open switches? Each earpiece has a sliding switch that can be used to change the D777LP from closed (noise-isolating) to open (non-isolating) mode. Although it's an interesting idea -- block external noise when you need to, but let in external sound when you want to hear what's going on around you -- the implementation is largely ineffective. Regardless of the environment, noisy or loud, I couldn't hear much, if any, difference between the two modes; only when no music was playing through the headphones and I was listening intently for external sounds did the "open" mode seem to allow additional sound in, and even then it's quite possible that I heard something only because I was trying to. Nor did the position of the switch change the quality of the audio produced by the D777LP.
If you're looking for higher-end headphones for home listening, similarly-priced models from Sennheiser (the HD 555) and Grado (the SR 125) are better-sounding options. But the D777LP's fold-up design and small size make these headphones more suitable for portable use, and they still offer pretty good sound quality. Impressive noise isolation also makes the D777LP a reasonable travel alternative for those who don't like noise-canceling headphones or in-ear-canal models.--Dan Frakes
Sony Altus MDR-D777LP