The Plus edition comes with a smart and practical carry case.
Sennheiser prove there’s still room for fresh thinking in headphone design!
Like many headphone manufacturers, Sennheiser don’t only operate in the studio and pro audio markets. They are also major players in consumer audio and hi‑fi, and the streams quite often get crossed. Sennheiser’s HD 650 open‑backed headphones, for example, are officially located on the hi‑fi side of the gulf, but they remain a popular choice for studio applications. On ‘our’ side of the divide, meanwhile, pro audio staples like the HD 25 MkII are now joined by the new HD 490 Pro. These cost slightly less than the HD 650 and, like that model, are conventional over‑ear, open‑backed, moving‑coil headphones. Unlike the 650, however, they are very much targeted at studio applications. So, although they are far from being the most costly model that Sennheiser make, the HD 490 Pros are in a sense the flagship model of their pro audio line.
It’s relatively easy to identify features that mark some headphones out as not being designed for pro audio: there’s no obvious studio role for wireless Bluetooth connectivity, active noise cancelling or integrated cable microphones, for example. But what, apart from a balanced, neutral sound, makes this new set of cans particularly well suited for audio engineering? Well, Sennheiser’s engineers have come up with several interesting design features that mark the HD 490 Pros out not only from other Sennheiser models, but also from rival products.
Case Study
The HD 490 Pros are available in two versions, the main difference being that the Plus edition comes with a very nice fitted case. Given the relatively modest price differential, I think it’s definitely worth spending the extra if they’re ever likely to come on the road with you. Plus purchasers also get a 3m cable as well as the default 1.8m one, and a spare for the removable foam pad that cushions the top of your head against the headband.
Talking of cables, one nice and arguably ‘professional’ feature is that both earcups have a mini‑XLR socket, allowing the cable to be plugged into whichever side is most convenient. A small plug closes whichever socket is not in use. Not exclusively professional but certainly very welcome is that these XLRs are four‑pin sockets, allowing the HD 490 Pro to be driven from balanced headphone amps if you have the correct cable.
Still talking of cables, the supplied mini‑XLR to jack cords are interesting in their own right (I can’t believe I just said that about a headphone cable). They are, at heart, straight cables, but with a short curly section located a couple of inches below the XLR. This, I assume, is related to one of the patented innovations that Sennheiser claim for the HD 490 Pro, which is a dramatic reduction in cable‑borne noise compared to conventional designs. It really works, too: flick the short section of straight cable above the curly segment and you’ll hear the usual annoying thumps and clicks. Do the same to the main part of the cable and the only sound you’ll hear is what reaches your ears acoustically through the HD 490 Pros’ open grilles.
And talking of grilles, Sennheiser also claim a long list of innovations relating to the design of the earcups and the drivers. These include a “geometrically angled earcup design” that “optimises transducer placement for a consistent listening experience”; an “innovative low‑frequency cylinder system for full, accurate, and clearly defined low end”; an “open‑frame architecture” which “reduces total harmonic distortion and minimises resonance”; and “Braille‑guided L/R earcups” for blind and partially sighted users. Their engineers have also, at long last, thought about the comfort of spectacle wearers, with “grooved ear pads for eyeglasses”.
Pad Reputation
It is reasonably well known that the geometry and the material of headphone earpads can make a significant difference to the sound of a pair of headphones, and there’s a thriving community of DIY headphone enthusiasts who like to experiment with different fabrics, fillings and dimensions. (Wait 'til they hear about Sennheiser’s new cable!) Uniquely, in my experience, the HD 490 Pros are supplied with not one but two different pairs. The factory‑fitted velour earpads can be swapped out for an alternative set of cloth‑covered pads. As usual, this is a straightforward process, with the replacement pads simply clipping into place. The two types are, respectively, designated the Producing and the Mixing earpads. Sennheiser publish frequency response plots which show that the velour Producing pads introduce a gentle low‑frequency shelving boost, starting at around 400Hz and about 4dB up at 100Hz. There are also differences of detail further up the spectrum, but nothing dramatic.
The main difference between the Producing and Mixing earpads lies in the low end.
Sennheiser say the choice is offered in response to one of those awkward dilemmas that plague manufacturers. If you ask audio professionals what they want, they’ll tell you they prize a neutral, uncoloured sound; but actual sales figures suggest that ‘warm’‑sounding headphones are more popular than truly neutral models. With the HD 490 Pro, you can have both what you say you want and what you actually want!
Comfort Listening
Most new headphones these days seem to be low‑impedance designs. With a nominal impedance of 130Ω, the HD 490 Pro are more so than the 300Ω HD 650, but still higher than most. Still, with a sensitivity of 105dBSPL for a 1Vrms 1kHz input, they shouldn’t present too many problems to mobile devices and other low‑powered headphone amps. Another intriguing contrast in terms of specifications relates to distortion: the HD 650s achieve a remarkably low THD figure of 0.05%, whereas the HD 490 Pros are merely very good, at 0.2%.
Unusually, one of the HD 490s’ most obvious competitors is also made by a company within the Sennheiser group. The Neumann NDH 30s are, likewise, open‑backed headphones targeted squarely at pro audio, and although they appear to have nothing in common design‑wise, their specified sensitivity and impedance figures are very similar. Once again, distortion is where the two differ, with the Neumann design nearly an order of magnitude better at 0.03% THD.
I don’t have a pair of HD 650s, but I was able to compare the review HD 490 Pros directly against the NDH 30s, as well as the Shure SRH1840s, my longstanding reference for neutral sound in open‑backed moving‑coil headphones. Having briefly tried the velour earpads, I quickly switched to the fabric ones and didn’t go back; to my ears, the sound is a hint on the warm side of neutral even with the Mixing pads. Very much like the Neumanns, there’s a gentle but noticeable bump somewhere in the 100‑150 Hz area, and in this case, it slightly overshadows what might be called the ‘true’ bass region below 100Hz. It’s subtle, though, and you get used to it almost immediately.
In the NDH 30s, this warmth is paired with a hint of softness in the midrange, most noticeable around 2kHz or so. That’s not at all the case with the HD 490 Pros, which to my ears are just on the confident side of neutral when it comes to midrange presentation. It’s a voicing that I find much more useful for music mixing and editing than the sparkly treble and exaggerated bass that some headphones deliver. It’s also very similar to the sound of the Shures. In fact, I’d say that the SRH1840s subjectively sit in between the Neumann and Sennheiser models from a tonal point of view, but rather closer to the latter. Depending on your preference, I can imagine that any one of the three might strike you as nailing your idea of ’neutral’.
And although the HD 490 Pros’ distortion performance may be inferior on paper to that of the NDH 30s, it certainly isn’t a problem in practice. If distortion is likely to be audible at all, it’ll be on music with heavy, low bass, and my journey through the world of Bass Boosted Punjabi Music playlists didn’t provoke any misbehaviour that I could detect. 808s go lower on the NDH 30s, though, which definitely have the edge when it comes to representing sub frequencies.
The HD 490 Pros present music, especially guitar‑based music, with a confidence and immediacy that puts a smile on your face.
I like the tonality of the HD 490 Pros, then; and I like lots of other things about them, too. I found them much more comfortable to wear than the Neumanns, perhaps even more so than the Shures: maybe that spectacle groove makes a real difference. I also really, really enjoyed listening to them. The HD 490 Pros present music, especially guitar‑based music, with a confidence and immediacy that puts a smile on your face. Yet at the same time, they’re certainly neutral enough for analytical listening. I must have listened to Parachute by the Pretty Things hundreds of times in the last 30 years, but I’d never noticed the strange noise near the start of ‘The Good Mr Square’ until I heard it through the HD 490s. And from a production point of view, I was particularly impressed with how they put across vocal sibilants. Many headphones exaggerate these or somehow mangle them; the HD 490s made them sound like the natural part of the human voice they are. In fact, they clearly bettered the Shures in this regard — so much so that I subjected them to the ultimate high‑frequency torture test, otherwise known as the tambourine at the start of the mono mix of ‘Hey Jude’. They passed with flying colours, leaving the Shures well behind and perhaps even beating out the Neumanns.
Bottom Line
The bottom line here is that if I had to mix on headphones, I’d be happy doing so with any of these three models. But the HD 490 Pros’ comfort, adaptability and very slightly mid‑focused tonality are all qualities that I personally find very appealing, and the bonus is that they are the least costly of the three. Especially if you work with the kinds of music that are recorded using microphones rather than made with synths, I think they are very hard to beat at the price.
Summary
The HD 490 Pros are bristling with innovation, aggressively priced, supremely comfortable — and they sound very, very good.
Information
£349 or £399 for Plus edition. Prices include VAT.
$399 or $479 for Plus edition.
