Ohmygosh. The first time I switched back to "regular" headphones after listening to Ultrasone headphones exclusively for a week, I was completely underwhelmed by the "small" and "constrained" sound of regular headphones. With Ultrasone's patented S-Logic Natural Surround Sound system, the music has much more depth; and individual instruments no longer sound like they're being played inside your head. Instead, you hear the individual sound sources in front of you, to your side, and even behind you! How do the folks at Ultrasone do it? You might guess that they're using multiple drivers, digital signal processing, or some other complicated technology-because the effect, although subtle, is immediately noticeable and quite flattering. Nope. Nothing that obvious. Nor complex. S-Logic is so simple a concept, I'm surprised it hasn't been done a thousand times over already. Here's the secret: the drivers (which, as far as I can tell, are conventional, voice-coil-driven diaphragms) are placed ahead of the ears so that the shape of the outer ear affects the sound waves as they enter your ears-just like when you're listening to a sound source that's many feet away. With conventional headphones, the drivers are right on top of your ear canals, so you no longer receive cues from the acoustic "signature" that your outer ears impart on the incoming sound. Neato! (And to be fair, Ultrasone has a gajillion patents behind this "simple" idea.) Other benefits of Ultrasone's technology? Reduced magnetic field emissions (up to 60% less than conventional designs) and safer hearing (due to the listener perceiving the same volume at lower dB‚s). Ultra-low emission versions (ProLine, up to 95% reduction) of their headphones are also available.
I've been using three different S-Logic models for the past few months. The HFI-650 is closed-ear, and it folds up for transport and folds sideways for one-ear cue'ing. The HFI-2000 is circum-aural, open-backed, and has the plushest earcups. The HFI-15G is a smaller, open-air headphone, suitable for mobile use. When it comes to headphones, I'm a big fan of the both the Sennheiser sound and feel-my favorite 'phone being my HD 414 reissue. But I also love everything in Sennheiser's current range. The Ultrasones are so similar to their Sennheiser counterparts in terms of comfort and build-quality, that I wouldn't be surprised if they're made in the same factory. And like Sennheisers, the Ultrasones have user-replaceable earpads.
Which Ultrasones do I like best? Tough question. The HFI-15G, the cheapest of the lot, sounds best to me. But unlike most people, I'm a big fan of midrange, and this has the smoothest midrange to me. Unfortunately, it doesn't stay on my head that well, and the snap-in mini-plug to 1/4" adapter comes off too easily. The HFI-2000 is the most comfortable, but its extended frequency response also comes with the brightest high end. The high end isn't too harsh, like on Sony MDR-V6 or MDR7506 headphones, but there's more of it than I personally care for. And getting them to fit my head required bending the metal tabs that hold the earpieces to the headband (after being advised to do so by Ultrasone's distributor). The HFI-650 works out best in a recording situation, being close- backed. On the other hand, my review sample came with a coiled cable, which I feel is too heavy and tangles too easily in a studio environment; but the manufacturer has since switched to a straight cable. What is good for the studio is the HFI-650's screw-on 1/4" adapter and the fact that it has the "biggest" sound overall. And it has enough high end to make critical decisions. You win some, you lose some. Details and nitpicks aside, the real benefit of these headphones is the S-Logic sound. Once you live with it, you'll have a hard time enjoying music on regular headphones. I'm hooked! (HFI-650 LE $229 MSRP, HFI- 2000 LE $249, HFI-15G LE $99;ULE versions are $50 more; www.ultrasone.com)