Sennheiser MOMENTUM Free Black review

This assessment covers Sennheiser's U.S. MOMENTUM Free Black, article 507490, also identified by the support code M2 IEBT SW. The manufacturer marks the product end of life and no longer sells it from its own U.S. page. This is an evidence-based review of the documented design, not a listening, fit, call or battery test. A present-day offer's condition, remaining battery capacity, package completeness, seller, warranty and return terms are unknown.

Black article 507490 is a neckband, not a case-based TWS system

The two sealed ear-canal pieces connect through a flexible cable with a control and battery section worn around the neck. A magnetic clasp can hold the earpieces together when they are not in use, and the manual says the cable can sit in front of or behind the neck. That makes the form factor easier to identify than the name alone: MOMENTUM Free is not the fully separate earbud-and-charging-case design implied by many current true-wireless products. The carry case stores the headset; the manual does not describe it as a charging case or a source of extra listening time.

Sennheiser's manual describes ear-canal coupling and says the medium ear adapters are fitted by default. It also explains how to change the adapter size and adjust the cable organizer. This gives a buyer concrete variables to verify—tip condition and fit, cable routing and control placement—but not a guarantee that the seal will be comfortable or secure for a particular ear. The manufacturer's image shows the black neckband, red accent cable and controls; it does not prove that a seller's used package includes the original tips, case or cable.

Codec support is broader than one device's guarantee

The exact M2 IEBT SW manual lists SBC, AAC, aptX and aptX Low Latency. A codec listed by the headset is only one side of the link: the phone, computer, operating system and chosen playback path must support and negotiate it. Sennheiser describes aptX Low Latency as a video-synchronization route when the host supports that codec; that is not a measured latency result or a guarantee for every app. The manual also identifies Bluetooth 4.2 and common audio/call profiles, but the feature list should not be mistaken for current multi-device software behavior.

One runtime distinction is easy to lose when several codecs appear in the same paragraph. The manual's specification table gives up to six hours in A2DP music mode and up to 8.5 hours in HFP talk mode. It does not assign the six-hour music claim to a particular named codec, so this assessment keeps it codec-neutral instead of treating it as an SBC-specific figure or copying it to AAC and aptX. Neither duration was independently measured here. The headset's built-in battery is specified as a 100 mAh lithium-polymer cell; an old unit's current capacity cannot be inferred from that original specification.

Plan for Micro-USB charging and no case reserve

The neckband charges at a Micro-USB input, with the manual giving about 1.5 hours for a full charge. A USB charging cable is listed among the package contents, while a power adapter is not listed as supplied. The carry case does not change that arrangement: there is no charging case in the documented package, no wireless-case option and no case-based battery reserve to add to the per-charge music figure. This matters if the shopping task specifically requires a USB-C or wirelessly charged case; the presence of a USB cable alone does not make the older neckband meet either requirement.

Remembered devices are not confirmed multipoint

The pairing section describes connecting to a Bluetooth device and automatically trying the most recently connected device when powered on. It also says the headset can remember up to eight device profiles. A remembered-device list is not proof of two simultaneous live source connections, and the reviewed manual does not describe a multipoint switching mode. If two-device handoff is essential, this model should not be treated as a confirmed match. Its inline controls cover volume and track changes, playback, calls and voice control; the manual notes that some smartphone functions may depend on host support.

ANC, water protection and condition remain boundaries

The exact U.S. product copy and manual describe Bluetooth playback and a sealed ear-canal design, but do not document an ANC mode. Passive attenuation from a fitted tip is a different thing from active noise cancellation, and the six-hour A2DP specification cannot be relabeled as ANC-on runtime. The manual's care section says to keep the headset dry and use a soft, dry cloth; it does not provide an IP water rating or a sweat/splash certification. Do not infer exercise or rain suitability from the fact that the product is worn around the neck.

Before comparing an older listing, match the exact black article 507490, inspect the battery and every included component, and check the seller's return terms. Sennheiser's model-specific service page says economical non-warranty repair is unavailable, so verify any repair or warranty representation rather than assuming replacement service. An offer may be new-old-stock or used; neither the historic feature sheet nor this review establishes its current state.

For the boundaries behind this assessment, see the Sennheiser U.S. product record, the M2 IEBT SW instruction manual and the model-specific service and spares page. Their descriptions are manufacturer evidence, not independent test results.