The Sennheiser HD 490 PRO: A $400 Open-Back Headphone Reference?

Last year, Sony introduced its MDR-MV1 Reference Monitor Headphones ($400), an open-back design aimed at professional sound engineers and music creators. And Audeze introduced the $400 MM-100 planar magnetic headphone with a similar target demographic. Now, Sennheiser has launched a direct competitor in the all-new HD 490 PRO reference studio open-back headphones ($399). Sennheiser says that the HD 490 PRO is “purpose-built for producing, mixing, and mastering.” The headphone is a circumaural design with a custom dynamic driver and two different sets of ear pads, which reportedly offer slightly different sonic presentations. The HD 490 PRO promises highly precise sound reproduction and a very wide and realistic sound stage, according to Sennheiser. These attributes should give producers, audio engineers, and musicians “the transparency they need for critical mixing decisions and for confidently resolving any panning placement issues,” according to the company. 

If you compare today’s music productions with that of ten, 20 years ago, you will notice how the massively increased computing power and complex parameter automation have changed the way in which music is made. In every genre, engineers and music creators are continuously pushing boundaries, creating extremely complex mixes that can be prone to so-called “audio blind spots.” Mixes can be crowded and muddy, with too many instruments sitting at the same position and their frequencies competing. For the engineer or musician, it becomes difficult to hear each individual instrument or voice distinctly. This goes to show the importance of a good pair of studio headphones.

— Jimmy Landry, Category Market Manager for Music Industry at Sennheiser

How Did Sennheiser Address the Needs of Audio Professionals?

Sennheiser’s engineers addressed the changing needs of audio professionals in a number of ways. The HD 490 PRO’s “extremely wide, dimensional sound stage” should help users to precisely localize the components of a mix, and the ultralight voice coils are designed to ensure a “fast and authentic” reproduction of the audio signal, according to the German company. Sennheiser’s higher-end headphones (such as the HD800 S) are known for an uncolored sound, though they are perhaps a little lean, tonally speaking, for my tastes. But in the context of a studio monitor headphone, that kind of clinical frequency response is sure to be useful, even if it might not be the most luxurious sound for music enjoyment purposes. Sennheiser says that the HD 490 PRO has an “honest frequency response across the entire audio spectrum,” with a low end that sounds full, yet accurate and clearly defined, thanks to an innovative “low-frequency cylinder system.” This unique feature helps users to pinpoint and resolve problems in low-frequency information, resulting in meticulously clear mixes and masters, according to Sennheiser. Like the aforementioned Sony and Audeze headphones, the HD 490 PRO benefits from an open-back design with mesh ear cup covers, allowing the sound coming off the back of the driver to escape into the open air. As a result, echoes, resonances, and bass build-up can escape without affecting sound quality, affording the user more detail and a more open, layered soundstage. Sennheiser’s take on this approach is called Open-frame Architecture, which not only minimizes resonances and distortion, but also optimizes the listening experience by placing the transducers at a slight angle relative to the ear, so as to better emulate a typical monitor loudspeaker setup.

All these features combine to enable music professionals to identify and resolve any panning placement issues and troublesome low-end frequencies – ensuring clear mixes and superbly refined masters. The HD 490 PRO studio headphones put you in full control of every detail.

— Gunnar Dirks, Sennheiser Product Manager

Sennheiser HD 490 PRO: Design

Any headphone design needs to be comfortable in order to be successful as a product, but comfort is perhaps even more important in professional headphones, which may be worn for many hours at a time, day in and day out. Sennheiser is an industry leader in headphone ergonomics, and the company tends to focus on reducing weight to ensure all-day comfort. There is an inherent tradeoff, of course. Lightweight plastic parts tend to be less robust than heavy-duty alternatives made of metal, so you might expect the HD 490 PRO to feel flimsy. But Sennheiser’s headphones have proven to be remarkably rugged, thanks to clever engineering and the use of high-quality plastics. The HD 490 PRO promises an ergonomic headband design that eliminates any pressure points, and circumaural ear pads with Sennheiser’s patented “soft comfort zone.” This feature reportedly provides comfort and a good seal around the temples, even for bespectacled listeners like me. There’s also a patent pending for the “special axes geometry” of the HD 490 PRO. Sennheiser says that this design ensures that the headphones optimally adapt to the head and maintain uniform contact pressure, regardless of the user’s head shape or size.

When you're creating music, the last thing you want is to be focusing on the fit of your headphones. The HD 490 PRO let you feel the music and forget about the headphones.

— Jimmy Landry

Sennheiser HD 490 PRO: Ear Pads

The HD 490 PRO includes two sets of ear pads. The velour-style pads are for “producing,” according to Sennheiser. These reportedly lend the headphone a slightly warmer response in order to “create perspective and help users make a holistic judgement of the sound.” The fabric ear pads are for “mixing,” and they are designed to yield a “very flat, neutral sound that helps dive into detail when a sound reference is needed in finishing off a mix.” Unusually, both types of ear pads are washable. That’s a huge bonus in a studio environment, where headphones are often used by many different people. They are also replaceable, of course, which should extend the headphone’s useful life many times over.

The development of the HD 490 PRO was preceded by the biggest professional headphone survey we ever did, where users voted neutral and flat reference audio as the most important feature. However, when we took a look at market figures, we discovered that a slightly warmer sound was preferred over a 100% neutral response. Therefore, we decided to give our customers two headphones in one – by providing two different sets of ear pads that were carefully designed to shape the sound differently.

— Gunnar Dirks

Sennheiser HD 490 PRO: Accessories

In addition to the two pairs of ear pads, the HD 490 PRO comes with a 5.9-foot detachable cable, which can be plugged into the right or left ear cup. The cable features a patented coil structure that prevents it from transmitting noise when it hits a desk or rubs against clothing. The HD 490 PRO Plus ($479) is the same headphone, but also comes packaged with a 9.8-foot cable, a carrying case, and an extra fabric headband pad in addition to the standard velour one. These accessories are all available for separate purchase, as is the optional balanced headphone cable ($39). Both the regular HD 490 PRO and the HD 490 PRO Plus include a free license for the dearVR MIX-SE plugin from Dear Reality, which turns a DAW (Digital Audio Workstation, such as Pro Tools) into “an ultimate virtual mixing environment, simulating the carefully designed acoustics of ideal mixing studios.” Sennheiser says that this plugin helps audio professionals to achieve “a balanced and consistent translation of their mixes on different systems.”

If you are looking for studio headphones that give you the transparency and excellent localization needed for crafting outstanding mixes, the HD 490 PRO are your choice.

— Jimmy Landry

The HD 490 PRO was designed in Germany and is hand-assembled in Romania.

More information: Sennheiser HD 490 PRO

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