The Sennheiser HD598's high-gloss burled wood accents, thickly padded headband, and ear cushions all lend a luxurious feel to the design. The tan-and-beige colour scheme is a nice alternative to Sennheiser's usual grey or black finishes. In addition to the HD 598 (AU$399), Sennheiser has introduced two less expensive 500 Series models: the HD 558 (AU$299.95) and HD 518 (AU$199.95). Sennheiser isn't the sort of company that jumps on trends; the goal for its audiophile-oriented designs is to make the most accurate-sounding headphones possible, and the HD 598 is the latest example of such thinking.
The HD 598 is a full-size, over-the-ear (circumaural) headphone. It weighs just 270g, but its mostly plastic construction makes it feel even lighter. We found the velvet ear cushions extremely comfortable, even over extended listening sessions. The HD 598 is among the most comfortable Sennheisers we've tested to date.
The HD 598 features Sennheiser's Eargonomic Acoustic Refinement technology, which uses acoustic baffles inclined at a slight angle to guide the sound directly to the ears. The technology appears to be derived from Sennheiser's flagship HD 800 headphone. The HD 598 also features powerful neodymium magnets, Duofol drivers and lightweight aluminium voice coils.
The headphone has a user-replaceable 3-metre-long cable, terminated with a 6.3-millimetre gold-plated plug, and you also get a gold-plated 3.5mm audio plug. Thanks to the clever attachment connection, the detachable cable isn't likely to accidentally fall out. Other than the colour difference and wood accents, the HD 598 is a near cosmetic twin of Sennheiser's highly regarded HD 595 headphones. The HD 598's impedance is rated at 50 ohms.
We listened to the HD 598 with an Onkyo TX-SR805 receiver, a Schiit Audio Asgard headphone amplifier and an Apple iPod Classic. The headphone's sound is super-clean and has a wide-open soundstage. Tonal balance is a little brighter and emits more treble detail than we've heard from previous generations of full-size Sennheisers. Even so, it's a very easy headphone to listen to over long listening sessions.
Deep bass on the Sennheisers has tremendous impact and power, so the big drums on Grizzly Bear's Vecktimest CD sounded terrific and the soundstage is remarkably spacious. The headphone's open quality works especially well with movies like Cairo Time. When Juliette Grant (Patricia Clarkson) first arrives in Cairo, she's picked up at the airport by her husband's friend Tareq (Alexander Siddig). As they drive away, the sounds of the busy city streets surrounded us, and the dialogue sounded exceptionally natural.
The Sennheiser HD 598 sounds fine with Crosby, Stills, Nash & Young's live album, 4 Way Street. The liveliness and clarity of the recording is well preserved by the headphones, but while the HD 598 can play loud with iPods, the drive may still fall a bit short for some listeners.
Still, we wouldn't recommend the HD 598 to buyers who only intend to use the headphone with an iPod or other portable music players. Bowers & Wilkins' similarly priced but smaller on-ear P5 headphone is more dynamic and transparent and has better bass definition used with an iPod, but we much preferred the HD 598's sound over the P5's at home plugged into a receiver or headphone amplifier.
Comparisons with Monster's Beats Pro full-size headphone easily demonstrate just how different two headphones can sound. The Beats Pro has a lot more bass punch and treble detail, which makes for a more "exciting" sound, but the HD 598 is a more accurate-sounding design. The Beats Pro contains the sound field within the listener's head, while the HD 598 allows the sound to appear from outside the ear cups.
We compared the HD 598 with our 10-year-old Sennheiser HD 580 headphones, and the company's sound "signature" is apparent on both models. The two headphones share a satisfying sense of clarity and a smooth frequency response without any over-emphasized bass or treble peaks. But the HD 598 has better resolution and detail with more dynamic life.