Sennheiser HDB 630 Review: Audiophilia With Trade-Offs

The Sennheiser HDB 630 aren’t the latest pair of high-end, premium-grade, closed-back wireless headphones to appear on the market and to make things challenging for the brand, they’re entering a market already saturated with these audio devices.

That said, Sennheiser is clearly offering more than just a single-point audio connection with the HDB 630. But in doing so – providing more of a package of premium quality and experience – there are trade-offs to owning this headset.

What Am I Looking At?

So, what do you get for RM2,599? For a start, a hard-shell, polygonal, triangular casing to house the HDB 630. The headphones themselves sport a simple design, literally. Compared to other premium wireless headphones I’ve reviewed, they look generic.

The headband is made from plastic and not metal, while the padding on it is from a new “Ideatex Japan leatherette”. Sennheiser believes this to be more durable than just simple plastic and should make it lightweight, although not necessarily lighter than its rivals. Weight distribution thus far is well-balanced, with just enough tension in it to ensure it stays on your head without feeling like a vice.

By the by, that “leatherette” material is also being used with the outside of the earcups, which makes them soft and comfortable enough for prolonged use. Internally, each earcup is fitted with a 42mm dynamic driver

Compared to most premium wireless headphones, the HDB 630 is undeniably feature-rich. Its Bluetooth module isn’t the most up-to-date at 5.2, but to make up for it, it comes with a BTD700 USB-C dongle; direct wired connectivity either through its 3.5mm cable or USB-C cable, and an equally feature-rich control panel via the Smart Control Plus app.  Interestingly, there is only one button installed throughout the HDB 630, while the rear of the right earcup acts as a gesture control pad that can be so goshdarn sensitive at times. More on that later.

What’s Good About It?

Out of the box, the HDB 630 sounds very neutral, or as my colleague puts it, flat, and he’s not wrong. That being said, and if I had to choose a pitch that stands out, I would say the lows are the strongest.

That doesn’t mean it’s back-of-the-skull-rattling strong or good. The tuba booms from Nina Simone’s Feeling Good deliver the punch, but again, not enough that I feel it reverberating around the back of my head. It’s the same story with the bass in Venus De Milo By Stacey Kent, and the walking bass line from Flight of the Cosmic Hippo by Bela Fleck and The Flecktones.

Balance between the pitches is imbalanced.

Outside of the lows, the highs and mids are clear, sharp, detailed, and don’t pierce your eardrums, but as I mentioned, some tweaking is necessary through the headphone’s app if you really want to make the most out of it. More on that later.  Out of the box, the vocals of Lose Control by Teddy Swims deliver on the sheer presence of his voice without breaking my eardrums. Sound staging is equally impressive, allowing me to place and hear the position of each instrument in TANK! By Yoko Kanno and the Seatbelts accurately enough.

The real upsell here is the BTD700 dongle that delivers 24-bit/96kHz level audio quality, although this is also delivered via a direct USB-C cable connection or through the headset’s dedicated line-in, but that dongle obviously takes away that clutter. That said, I wouldn’t recommend using it for virtual meetings on the PC; you’re still using the integrated microphones of the headset and having used it a couple of times, the complaints were that my voice sounded either faraway, muffled, or scratchy. In other words, it works fine on Bluetooth, but not the dongle.

Another one of its biggest upsells is the battery life. Sennheiser claims 60 hours of battery life for the HDB 630 with ANC on. As my daily driver, that claim holds water: I can enter into a flow state during work and have these headphones on with music playing at around 30% volume. That’s more or less about five hours at a time, each day.

Off the clock, that’s another five hours of continuous listening via the headphones, be it music or video on YouTube or Netflix. So, about 10 hours everyday, translating to six days of listening time, on average, before needing a recharge.

But the real star of these headphones is the pitch control you get from the dedicated Smart Control Plus app. This isn’t anything new on Sennheiser’s part but the ability to dynamically adjust the intensity and desired pitch makes these headphones desirable.

What’s The Catch?

This is perhaps the peak of nitpicking on my part, but the overall design of the HDB 630 looks and feels, in my opinion, terribly bland. I mean, sure, a case can be made about Sennheiser focusing on delivering more than just premium audio, but even that has its own set of caveats.

That segues us nicely into the next part: audio fidelity and performance. As I stated, both highs and mids sound neutral or, as my colleagues put it, flat. These headphones’ strongest pitch is the lows, but even then, it’s not the sort of skull-rattling experience that I have come to expect from premium headphones such as these. In the Hell Freezes Over rendition of Hotel California by The Eagles, I can hear the pluck and strumming of each guitar, but it somehow lacks the warmth and richness that the track exudes.  It is only after I have tweaked the EQ in the Smart Control Plus app that I can attain the desired wavelength that adequately envelops the entire spectrum of my palette.

Headband isn’t vice-level tight, but you begin to feel it after a few hours.

While the HDB 630 aren’t the heaviest or lightest headphones, you will start to feel the tautness and tension of the headband, especially over prolonged periods of use. I’m not saying your head will feel like it’s being crushed by a vice, but honestly, Sony’s WH-1000XM6 and the B&W Px7 S3 feel comfortable in comparison.

I also take some issue with the capacitive touch panel behind the right earcup and, more specifically, some of its gestures. The pinch-to-zoom gesture, in particular, isn’t quite as functional and sometimes, I don’t even know if I’ve increased the strength of the ambient passthrough. On that note, volume control isn’t incremental, but rather, swiping up or down on the earcup increases or decreases the volume by a huge jump, instead of incremental steps.

Still on the touch panel, the gesture control panel of the HDB 630 is so sensitive that even an accidental touch by my right hand would pause whenever I’m listening. It’s a minor irritancy at best, and doesn’t affect the overall performance, and I just thought that I should point this out. Compared to the WH-1000XM6’s, though, I’d say that Sony does it better.

And then there’s its ANC and ambient mode. Again, using Sony’s current flagship, the WH-1000XM6 as a baseline, the HDB 630 doesn’t feel quite as potent in its delivery. Even while active, the headphones don’t really block out all outside noise, and ambient mode really just makes everything sound muddy and incoherent when active.

Should I Buy It?

As a pair of premium wireless headphones, there are actually other headsets I can recommend for its asking price of RM2,599, all with, dare I say it, better audio quality, overall design, and far superior ANC as well. But again, Sennheiser is offering more than just audio fidelity with the HDB 630.

Beyond Bluetooth connectivity, the HDB 630 is offering dynamic, on-the-fly EQ tuning; 24-bit/96kHz audio fidelity via a USB-C dongle; and much, much longer battery life than any other brand is able to offer.

At the end of the day, I think Sennheiser also purposely tuned the HDB 630 the way it did as a way of giving fans and audiophiles the versatility to fine-tune their personal audio signature and preference. Personally, while these aren’t the best wireless headphones in the market, I still think they can give the competition a run for their money.

Photography by John Law.