Fitness earbuds that lack finesse

Sennheiser could have just released a set of wireless headphones with an IP55 rating, and that Momentum Sports (330 dollars), but went even further by adding heart rate and body temperature sensors to headphones designed for exercise. These add-ons give you more information about workouts, but also provide information to your existing third-party activity programs. Of course, the Momentum Sport should also excel in conventional headphone materials and offer an ergonomic design, active noise cancellation (ANC), touch controls, and other common features. Sennheiser has a solid track record with sound quality, but now has to balance that with the expanded capabilities of the Momentum Sport.

What’s so good about the Sennheiser Momentum Sport?

The overall shape of the Momentum Sport is the Sennheiser I like to use Momentum True Wireless 4. The rounded profile of the former fits my ears better and feels more comfortable, even though they are slightly larger. Without the matching wing, the Sport version still sits nicely on my ears, though this extra piece helps keep them in place during workouts. Simply put, this design looks sleeker and I’d love to see the company take a similar direction on its flagship model.

Sennheiser says it’s designed for “vibrant sound and impactful bass” to help power your workout, and it delivers. Stock regulation is noticeably lower at Justice’s hyperdrama, enhancing electronic melodies with a thicker tonal layer. This is definitely something that helps your energy levels during physical activity. But as I’ll discuss later, extra bass isn’t always a good thing.

The Momentum Sport’s marquee features like heart rate and body temperature tracking work well. Thanks to the secure placement of the headphones, you can get constant, reliable readings in Sennheiser’s Smart Control software. The heart rate numbers matched the readings on the Apple Watch and I confirmed my temperature with a forehead scan. The Momentum Sport’s readings were consistent with the other devices every time, indicating the headphones are just as reliable as other in-home alternatives.

What’s more, there’s tight integration with apps like Polar, Peloton, Strava and Zwift, so you can use Momentum Sport with their devices, rather than the Sennheier app, which is mainly designed to adjust settings. However, only Polar’s Flow Momentum Sport supports body temperature tracking. Sennheiser says this is because Polar is the only company ecosystem stores tokens in this metric and supports relevant sensors. Regardless of which third-party app you prefer, you’ll probably want to sync the Momentum Sport with one of those, since the Smart Control app only displays real-time readings and doesn’t track trends or stats during workouts.

Although it needs to power more sensors, the Momentum Sport still delivers solid battery life. Sennheiser says that a single charge provides five and a half hours of playback, and that claim holds true. I had no problem hitting that number when I tested the volume looping around 65-70 percent volume. ANC is in normal mode and heart rate and body temperature sensors are active. The company says you can extend the Momentum Sport’s battery by 30 minutes if you activate Eco mode in its app. This feature disables aptX audio and both body tracking sensors.

What’s not so good about the Momentum Sport

The Momentum Sport lets you touch your cheek for playback and call control. This is convenient when running, for example, you don’t have to find the exact location of the touchpad when you’re on the move or wearing gloves. The downside is that it can be activated by chewing. It’s intensely annoying. During my tests, chewing gum or food often triggered the controls.

Sennheiser says I have strong jaw muscles (okay?) near the sensor, but that doesn’t make it any less crazy. I chew gum during both runs and lifting sessions, so this is a deal breaker. Just clenching my jaw didn’t trigger it, so at least there’s that. The only way to fix the problem is to disable the on-board controls entirely, which disables both cheek tapping and the more common earbud tapping gestures.

The Momentum True Wireless 4’s ANC performance is solid but not amazing, and that’s true of the Momentum Sport. Both sets of headphones work the same way with constant noise sources, reducing the volume of external hum rather than completely blocking it out. Like a lot of the competition (and the True Wireless 4), the Momentum Sport struggles with human noise. Overall, none of them offer the powerful, world-silencing power that Bose and Sony muster.

The transparency mode on the Momentum Sport works, but it’s not great. The headphones allow for good surrounds, but don’t carry enough of your voice, and I found myself shouting during a few calls. There’s also an anti-wind mode, which is useful during outdoor workouts, but it’s a feature that almost all new headphones come with these days.

Unfortunately, good audio performance is not universal in the Momentum Sport. While some albums are detailed and crisp with added bass, others lack highs and a strong midrange. The sound profile suppresses things like stale, distorted guitar and bass lines. Vocals are consistently cut, but the more prominent kick drum on songs like Knocked Loose’s chaotic “Suffocate” relegate the guitars to the backseat. In fact, guitars in a variety of styles, including alternative, rock, and country, lack the depth and detail that the Momentum 4 provides. By dialing down the low-end tone, Sennheiser has sacrificed some of the speakers that usually make their headphones sound so good. And in a $300+ headset, that’s a shame.

Finally, let’s discuss the case, which is less complicated than Sennheiser’s previous designs. These headphones cost $330, and the charging case shouldn’t feel that flimsy. The lid usually closes securely, but the hinge is just a piece of rubber, so the case won’t stay open unless you lay it completely flat. The soft-touch coating feels nice, but compared to the accessories that come with the Momentum line, this case is just what I’d expect from a headset that costs half the price. The good news is that there is wireless charging support and the case is IPX4 rated, so all is not a loss.

Collection

The Momentum Sports presents a dichotomy. On the one hand, they’re great workout headphones that reliably track biometric stats to give you an inside look at your workout routine. On the other hand, they don’t have the overall sound quality I’ve come to expect from Sennheiser’s Momentum line, and the overly sensitive controls are an extreme nuisance. The headphones could be improved with some software tweaking, but for now they’re too expensive to buy just for workouts and don’t perform consistently enough to even be your main set.