Sennheiser HDB 630 Review

Design

• Different headband design
• Comfortable
• Sensitive touch controls

Like the Momentum 4 Wireless before it (still available at a killer price, I should add); these headphones aren’t aesthetic pleasers. The only clearly difference between the Momentum 4 Wireless and the HDB 630, is the silver linkages that connect the headband and earcups. Fancy dan headphones these aren’t.

But, given that these are for the audiophile and not for the casual audience, its plain, anonymous looks can be forgiven. Like many of Sennheiser’s recent headphones, the focus has been on ergonomics rather than standout looks.

In that regard, Sennheiser has met the mark as they are comfy to wear. Sometimes the left earcup can be a bit tight, but a few adjustments is all that’s required to sort that issue out. The clamping force isn’t too tight despite the headphones sitting firm against my temple, the soft earpads offering a cushy point of contact.

It’s not necessarily a plush, luxurious feel but it gets the job done with minimum fuss. Compared to the more expensive Bowers & Wilkins Px8 S2, they feel comfier.

The headband is sturdy without causing undue pressure. There’s an adjustable slider if the fit isn’t suited, though interestingly, the HDB 630 doesn’t have the fabric cover the Momentum 4 Wireless did, making it look plainer and more inconspicuous. It would have been nice if the premium sound was matched by premium looks.

The carry case that comes with the headphones is thicker and slightly bigger, with more pockets to keep stuff stowed away with its multiple cables and adapters. They don’t fold either, so if you want to keep them safe from scuffs and marks, into the carry case they go.

The arrangement of physical buttons is the same, but the HDB 630 relies on touch controls and swipes. They’re not always the most precise as there have been a few times when swipes seem to register but nothing happens. It’s still an area that needs improvement.

There’s only one finish – black – which adds to the audiophile feel of the Sennheiser HDB 630. It also comes with a dongle, which allows for higher quality audio over a Bluetooth connection. It’s something I think more headphone brands should include to get past the restrictions of some restrictive ecosystems but I’d have liked a Wi-Fi connection like the AKG N9 headphones offer.

Features

• Smart Control Plus app
• Parametric EQ
• BTD 700 Bluetooth dongle

There are a host of features tucked away in the Smart Control Plus app. Visually it’s the same, and it operates the same way as the original Smart Control app, with a couple of features that aren’t present in the original version.

Those include the Parametric EQ, which offers much finer control of frequency boosts and cuts than a standard graphic EQ. If you know what you’re doing you can mould the sound with more precision and hear the effects in real-time.

There is access to EQ presets if you’re not the type to fiddle around with settings, as well as Sound Check where you play music and are presented with options to tune the sound. Perhaps it’s me, but I can’t hear much, if any difference between the options. Bass boost and Podcast sound modes are included too.

The Crossfeed feature allows you to blend the left and right channels, and the effect is so simple and I find worth enacting to see if you like it. You can control the noise-cancellation (more on that later), customise the controls and the overall performance with features such as Head Detection, Smart Pause, and Comfort Calls, which apparently gives calls a more “natural sound stage”.

Sound Zone is not too dissimilar from the Adaptive Sound Control in Sony’s Sound Connect app. It automatically changes ANC and audio presets depending on your location, and you can create up to twenty of these Sound Zones, which could include places such as your workplace, home, college etc. Set them up and the headphones will do it all for you (but you do need Location enabled).

The Bluetooth dongle (or BTD 700) is perhaps the most interesting feature. The potential it offers is quite large as you can use, say, an Apple iPad Pro, and with the USB-C adapter bless it with the ability to play audio over an aptX Adaptive Bluetooth connection.

The USB-C handles the audio side, transmits it to your headphones, and presents what would have been AAC audio in higher fidelity. You can connect it to your personal laptop, a non-aptX compatible smartphone – whatever audio device that has a USB-C but no wireless high-res audio support.

It can be a bit stubborn, though.

Initially I had no problems connecting my laptop to the BTD 700 dongle. Connecting to another laptop and the dongle wasn’t having it. Re-pairing and resetting didn’t work but eventually restarting the laptop was all that was needed to give it a kickstart.

You can use the smart control app on a mobile device while the headphones are connected to another device via the dongle, but I couldn’t hear changes I made on the app reflected in the headphones, so I can’t say with confidence that it has any effect. There’s no Windows or Mac desktop version of the app, which seems a slight oversight on Sennheiser’s behalf.

It’s also worth noting that even though the Sennheiser HDB 630 supports Bluetooth multipoint, the BTD 700 dongle isn’t a separate connection. If you have three devices and the dongle is one of them, you’ll have to make sure it’s selected to hear any sound.

Bluetooth is supported up to the aforementioned aptX Adaptive, but the HDB 630 hasn’t abandoned listening with USB-C and 3.5mm audio cables included (as well as a decent in-flight adapter). The wireless performance mirrors that of the Momentum 4 Wireless – the signal doesn’t break but you can hear the soundstage shrink slight when it comes across wireless interference.

Noise-cancellation

• Wind noise reduction
• Transparency mode
• Adaptive ANC

The noise-cancelling performance is an improvement on the Momentum 4 Wireless, especially when dealing with lower frequencies. However, compared to the Sony WH-1000XM6 and the Sony is a fraction quieter overall.

The Bose QuietComfort Ultra Headphones Gen 2 are better too, suppressing noise with more confidence on an airplane. There’s an extra layer of noise that the Sony and Bose seem to deter that the Sennheiser lets in, but the difference is small rather than large.

I have found the performance can fluctuate in real-world environments. Using them on public transport and they’re not as quiet as I had anticipated but they do get rid of most noises, and they cancel noise without producing that artificial sound that less expensive headphones do. They are stronger than more expensive pairs, like the Focal Bathys MG, and they’re better than the similarly priced Bowers & Wilkins PX7 S3

Wind noise is dealt with adequately – it’s optional to toggle on in the app, and while it won’t remove all wind noise, it’ll reduce any rustling and turbulence when it’s on. The transparency mode is also fine, not the clearest or most detailed, but clear enough to get a sense of your surroundings.

Sadly, call quality is a disappointment. While the person on the other end could hear my voice, they also hear everything else. All the sounds around me were competing for attention, and the headphones struggle when it’s loud and noisy.

This is a common trait for headphones, but models like the Sony WH-1000XM6 cope with it better than the Sennheiser does.

Battery life

• Up to sixty hours
• Fast-charging support

One of the headline features about the Sennheiser Momentum 4 Wireless was its endurance. Up to sixty hours on a single charge and the HDB 630 reach similar levels, though this comes with a caveat I didn’t realise all those years ago. The sixty hours is when you’re listening to standard resolution audio…

Listening to wireless hi-res audio via the dongle, and it’s actually up to 45 hours. Always read the small print.

Having carried out my battery drain test with the headphones set at 50%, and playing from a Spotify playlist shuffle, it took 3.5 hours for the headphones to drop to 90%. That’s a good performance, and granted the drops could be even less if I kept the test going, but that suggests a performance in the region of 35 to 40 hours – similar to the results I got from the Momentum 4 Wireless.

There’s fast charging support, with a ten minute drive providing seven hours of battery life.

Sound Quality

• Balanced across the frequency range
• Not the biggest bass performance
• Airy, spacious soundstage

There’s no shortage of competition at this price. You got the Sony WH-1000XM6, Bowers & Wilkins Px7 S3 and Bose QuietComfort Headphones Ultra 2 all claiming to offer premium sound. How does the Sennheiser HDB 630 shake up? Pretty well.

The soundstage it paints is wide, with a clear, crisp approach to audio that brings clarity to voices. The sound is well balanced across the frequency range – not necessarily flat, but a neutrality that avoids the warmth and smoothness of the Momentum 4 Wireless.

Compared to the older pair, the soundstage is bigger and wider, with the HDB 630 offering slightly more insight with vocals, though it comes across as a little more gentle at describing the lows. The bass is more articulate and clearer – in fact voices and instruments all sound clearer than they do on the Momentum 4 Wireless.

There is a change the soundstage as well, a different focus in terms of depth as the HDB 630 comes across as flatter. Is this good or bad? I’m not sure, but it retrieves and picks up detail better so consider it good.

The highs are bright, sharp and clear and escape the smoothness that the Momentum 4 Wireless brought to highs. The older headphone sounded a little warmer, less detailed and clearer – the HDB 630 offers more insight.

The levels of insight are the biggest takeaway from the Sennheiser HDB 630’s performance, as well as sounding more natural. Frank Sinatra’s voice in Fly Me to the Moon has a crisper, more revealing tone; the double bass has more weight when it enters fray. The HDB 630 may not offer as much bass as the Momentum 4 Wireless, but the performance is more varied and articulate.

A listen to Maye’s La Canción and the low frequencies are treated with more reverence, and some may prefer the Momentum 4 Wireless’ bass performance; but you do have the Parametric EQ at your disposal if you want to make changes.

When pitched against the PX7 S3, a pair of headphones that I thought were one of the best-sounding models of 2025, the Sennheiser can’t match its loudness and energy – it doesn’t have the drama, energy or spectacle of the PX7 S3.

The PX7 S3 offer a hearty thump with the bass, with more power and solidity with the lows, but the soundstage isn’t as well organised as the Sennheiser, and the HDB 630 summons greater levels of insight.

The energy of the PX7 S3 can scramble detail while the gentle sound of the Sennheiser allows it to pick out the smaller details. Two different approaches, but I think I might prefer the Sennheiser if I wanted to hear everything, and the Bowers if I wanted to be entertained.

And when faced against the Sony WH-1000XM6, the Sennheiser has better control over the high frequencies but in terms of detail across the frequency range, the Sony is a match if not slightly better.

There’s more bass power with the Sony but the Sennheisers have a naturalism and clarity that’s less obvious on the WH-1000XM6. They are capable of more subtlety, a lighter and defter sound but the Sony offers more attack and energy. I might just prefer the Sennheisers with their natural, musical sound that, surprisingly, makes the Sony sound slightly compressed.

Listening over the Bluetooth dongle and the same traits apply, not quite the same infectious energy as other wireless models, but an airiness, crispness and spaciousness to the soundstage that engages. A little more energy and power to the low end wouldn’t go amiss though.

That said, plug these headphones in with a 3.5mm or USB-C connection, and these headphones sound tighter, detailed and, at least with the USB-C input, energised. Either way, it’s an enjoyable sound, whichever method you use to listen to music through the Sennheiser HDB 630.

Should you buy it?