Sennheiser MOMENTUM True Wireless 2 (Black 508674) review

Which MOMENTUM True Wireless 2 is covered?

This assessment covers the earlier U.S. Black MOMENTUM True Wireless 2, support model M3IETW2, article 508674. Sennheiser separately identifies White article 508831; the reviewed sources show no functional difference between those two finishes. They are not the original, unnumbered MOMENTUM True Wireless (M3IETW) and should not be treated as one generation. Sennheiser's U.S. page labels this family end of life. That is useful context for an older model, not proof that no retailer has stock or that a particular second-hand set is complete or working.

This is a source-based comparison of the manufacturer's U.S. product record, model manual and support answers, not a hands-on review. The second generation adds documented active noise cancellation (ANC) to its sealed in-ear arrangement. Its important limits are unusually concrete: the seven-hour playback claim is an ANC-off example, the charging case is wired-only, and the Bluetooth audio link handles one source device at a time.

Fit, passive isolation and ANC are related but not interchangeable

The manual describes ear-canal coupling and includes four silicone adapter sizes, XS through L, with M fitted before use. It instructs the wearer to seat the tips snugly and turn the earbuds slightly. That sealed geometry provides passive attenuation, while a separate feed-forward ANC system uses one microphone in each earbud to reduce ambient noise, particularly lower-frequency sounds. Sennheiser also provides Transparent Hearing, which routes outside sound through the microphones so a wearer can hear a conversation or announcement without removing the buds. It is an awareness mode, not open-ear construction and not the opposite of a sealed fit.

Fit matters to both sound isolation and the maker's stated ANC effect. Four tip sizes are a useful adjustment range, but the product documentation cannot establish which size will seal comfortably in an individual's ears. Nor is an ANC claim a promise that every sound disappears: the maker's own explanation distinguishes lower-frequency cancellation from higher-frequency reduction that depends more on the passive seal. The Smart Control app provides setup and adjustment for features such as Transparent Hearing and equalization; basic Bluetooth listening and calls are also described without the app.

Classic Bluetooth, codecs and device switching

The manual lists Bluetooth 5.1 and SBC, AAC and aptX for Bluetooth audio. Those are alternative Classic Audio codecs, not a simultaneous mode or a guarantee that a particular laptop or phone will negotiate aptX. The playback device and its software must support the chosen codec. The model does not have a documented LDAC or LC3 path in the reviewed source set.

Stored pairings are not multipoint. Sennheiser says the earbuds can remember as many as eight Bluetooth devices, but they connect to only one device for audio at a time. The app may maintain a separate Bluetooth Low Energy control connection; that does not turn the model into two-source audio multipoint. Switching the audio source requires changing the connection rather than expecting two computers or a computer and phone to remain ready for seamless handoff.

Calls use a two-microphone beamforming array, and the support FAQ advises adjusting the earbud angle so the microphone opening is not blocked. That is setup guidance, not a measured call-quality guarantee. The manual also documents a one-sided use restriction: the right earbud can work by itself, but the left cannot work alone because the right is the primary Bluetooth earbud.

Read the battery figure as a controlled example

Sennheiser gives approximately seven hours of earbud playback under a specific example: AAC, an iPhone within one metre, volume at 50 percent, Transparent Hearing off, ANC off and no customized equalizer. Its case-assisted total is about 28 hours, including up to three additional earbud charging cycles; the manual's quick-charge claim is about 1.5 hours of playback after ten minutes of charging. These are manufacturer specifications, not measurements from this review. In particular, the seven-hour number does not answer how long the model plays with ANC enabled; no ANC-on duration is established in the checked specifications.

That distinction matters for both filtering and resale. A stated minimum of even one hour of ANC music should not be inferred from an ANC-off figure. The manufacturer says the earbuds' and case's batteries are not exchangeable, so the original runtime cannot predict the remaining capacity of an older unit. Ask the seller about actual charge behavior, pairing, return terms and any warranty rather than relying on a product-page maximum.

Case charging, IPX4 and ownership checks

The case charges over USB-C and Sennheiser explicitly says the MOMENTUM True Wireless 2 does not support wireless charging. Its FAQ assigns IPX4 splash resistance to the earbuds and says the case is not splash resistant. That is not a waterproofing claim: the guidance says not to submerge or shower with the earbuds, and to dry wet buds before docking them. Treat the buds and case as different components with different protection boundaries.

The manual's original package list includes the left and right earbuds, M3IETW2 C case, a short USB-C-to-USB-A cable, four silicone tip sizes and printed guides. That describes what the maker listed for a new package; it does not prove what an older listing contains. Match article 508674 for Black or 508831 for White, check that both earbuds pair with their case, and confirm the actual cable, tips and return policy. Sennheiser's Black article support page says non-warranty repair service is unavailable, and the batteries are non-replaceable, so a seller's vague assurance should not be mistaken for a repair or battery guarantee.

Who should consider it?

The MTW2 is a plausible earlier-generation candidate for someone seeking sealed tips, documented ANC, Transparent Hearing and a Classic Audio codec option such as AAC or aptX. It is a poor fit when two-source Multipoint, LC3, wireless case charging, a case water rating or a quantified ANC-on runtime is essential. Its fit and features may be attractive on paper, but a listing cannot establish personal comfort, a well-sealed tip, the condition of a non-replaceable battery, or what accessories the seller actually includes. Evaluate the exact Black or White article and package, not just the shared family name.