Editor's note: The Ultrasone's HFI-650 has since been discontinued and replaced by the Ultrasone HFI-780.
Ultrasone's headphones sound different from all the other headphones we've heard. Conventional models direct most of their sound into your ear canals, but the German company's patented S-Logic process uses decentralized transducer positioning to spread sound over your outer ear in an attempt to mimic sound heard over speakers. The $249-list Ultrasone HFI-650 headphones mostly succeed in that mission; they sound terrific.
The HFI-650s' closed-earcup design offers a high degree of acoustic shielding, so you can enjoy DVDs or music without disturbing other people. Ultrasone headphones are popular with recording-industry professionals who demand not only accurate sound, but also rugged construction quality. The leatherette earpieces and headband are padded for your comfort, and, at 9.3 ounces, the HFI-650s are fairly lightweight. An extralong 10-foot cable, terminated with a 1/8-inch stereo minijack, is included along with a screw-on 1/4-inch adapter. You'll also appreciate that the headphones can be folded for compact storage. For $50 more, the HFI-650 Proline model is available; it's slightly heavier, and Ultrasone claims the beefier design reduces electromagnetic radiation by up to 98 percent.
The HFI-650s shined in our DVD trials. The weightier sound immediately trumped our reference Grado SR125 headphones, so we felt more of the action on the Spider-Man DVD. The wrestling match in Chapter 10 thumped and bumped with newfound authority, and thanks to the S-Logic, the roaring crowd seemed farther away. The bass wasn't merely powerful, it was highly defined, with far greater impact than AKG Acoustics' mighty K 301 Xtras, or even Ultrasone's top model, the HFI-2000s.
The HFI-650s were a revelation on our iPod, because the sound was huge, with incisive detail and visceral dynamic impact. Bass was subwoofer deep without sacrificing definition. The biggest surprise was the stereo imaging--the iPod's sound was bigger and wider than we're used to--so, yes, the S-Logic feature really works. These are very efficient headphones that will get plenty loud with flea-powered MP3 players. They're highly recommended.