Ultrasone has carved out a notable niche in the high-end headphone market since its founding in 1991. One of its latest models is the HFI-680, a full-size pair of headphones that retails for around $220. The HFI-680 is a handsome design, and its build quality is about average for a model in this price range. (For what its worth, many of the Ultrasone headphones we've tested over the years were made in Germany, but the HFI-680s are made in Taiwan.)
The central part of the HFI-680s' outer earcup is covered by machined metal; the other side that faces your ears features an oval faux-leather covered cushion. We like the oval shape because it better conforms to the ear's natural contour, which is an improvement over the round earpads featured on other Ultrasone headphones. Some people may find the faux leather makes their ears perspire in the summertime, but we didn't have any problems on that front.
The sturdy padded headband adds to the design's overall comfort. A 10-foot headphone cable is permanently attached to the left earcup; the cable is terminated with a standard 3.5mm mini-plug and there's a screw-on 6.3mm adapter. (There's also a second 6.3mm-to-3.5mm adapter, too, but why you wouldn't simply remove the first adapter instead is beyond us.) The HFI-680s can be folded for compact storage, and Ultrasone includes a soft carry bag and an Ultrasone produced demonstration disc of music.
The headphone features Ultrasone's S-Logic Natural Surround Sound Plus technology that bounces the 40mm gold-plated driver's sound off your outer ear (instead of firing directly toward your eardrum). Ultrasone claims the technology produces a less headphonelike sound, so it's a little closer to the sound of speakers. We can't say that's what it sounded like to us; the HFI-680s were more "closed in" and sounded more canned than comparably priced Sennheiser and Grado models, which use an open-back design instead.
To that point: one definite advantage of the HFI-680s' closed-back design is that it hushes outside noise. It's not as completely isolating as a bona-fide noise-canceling headphone, but it gets you halfway there. The isolation also works in the other direction, limiting how much of the headphones' sound will be heard by people around you.
The HFI-680s, like all of Ultrasone's headphones, feature what the company calls "ULE technology" (ultralow emission). The company claims that most headphone drivers produce low-frequency magnetic fields. Ultrasone employs MU Metal shielding (a nickel iron alloy), which--again, according to Ultrasone--reduces magnetic radiation by up to 98 percent compared with other headphones. It all sounds quite impressive, but we have no way of independently verifying it.