Google Pixel Buds 2a / Sennheiser MOMENTUM 4 Wireless

Google Pixel Buds 2a: Pixel Buds 2a in-ear earbuds with a USB-C charging case; the Fog, Berry, Iris and Hazel colours share the same hardware. The Pixel Buds A-Series and Pixel Buds Pro 2 are separate models.

Sennheiser MOMENTUM 4 Wireless: MOMENTUM 4 Wireless over-ear wireless headphones; Black (509266), White (509267), Graphite (700383) and later Brown, Teal, Copper and Denim colours. MOMENTUM True Wireless in-ear models and MOMENTUM 3 Wireless are separate products.

SpecificationGoogle Pixel Buds 2aSennheiser MOMENTUM 4 Wireless
Release year20252022
TypeIn-ear true wireless; wing-tip stabiliser, four ear-tip sizes (XS, S, M, L) GoogleAround-ear, closed-back, wireless; active noise cancelling

The ear pads fully surround the ear; Sennheiser cites a lightweight design, padded headband and deep cushioned earpads for long-wear comfort.

Sennheiser
ProcessorGoogle Tensor A1 in each earbud Google—
Driver11 mm dynamic driver Google—
Noise cancellingActive noise cancellation (Silent Seal 1.5); transparency mode; active in-ear pressure relief

Pressure relief adjusts pressure in the ear canal to reduce the blocked feeling of a sealed in-ear design.

Google		—
ConnectivityBluetooth 5.4; pairs with Bluetooth 4.0+ devices

Full features need an Android 6.0+ phone and a Google account; on iPhone basic listening works but app settings are unavailable.

Google		—
CallsTwo microphones per earbud; Bluetooth super wideband; Clear Calling; wind-blocking mesh

Super wideband carries a wider audio range on calls with compatible Pixel phones.

Google		—
BatteryANC on: 7 hours (20 hours with case); ANC off: 10 hours (27 hours with case); 5 minutes of charging gives 1 hour Google—
Charging caseUSB-C charging; no wireless charging listed Google—
DurabilityEarbuds IP54, case IPX4

IP54 protects against dust and splashing water; the earbuds are not designed to be submerged.

Google		—
SensorsCapacitive touch controls; IR proximity sensor for in-ear detection; Hall sensor in the case Google—
Size and weightEarbud 23.1 × 16.0 × 17.8 mm, 4.7 g; case 50.0 × 24.5 × 57.2 mm, 47.6 g with earbuds Google—
UpdatesAutomatic security updates for at least three years from first availability on the US Google Store Google—
ColoursFog, Berry, Iris, Hazel Google—
Driver and frequency response—42 mm dynamic driver; 6 Hz–22 kHz; 106 dB SPL (1 kHz / 0 dB FS)

The frequency range describes measurement limits; the sound you hear is also shaped by the in-app equaliser and sound personalisation.

Sennheiser
Impedance—Active 470 Ω, passive 60 Ω Sennheiser
Noise cancelling and microphones—Adaptive hybrid ANC; 4 microphones in total (2 per side, MEMS, beamforming; 50 Hz–10 kHz); anti-wind mode; transparency mode

Hybrid ANC uses both outer and inner microphones; adaptive mode changes the level of cancellation to match ambient noise.

Sennheiser
Bluetooth and codecs—Bluetooth 5.2, Class 1; A2DP, AVRCP, HFP; SBC, AAC, aptX and aptX Adaptive

aptX Adaptive works only with Android phones that support it; iPhones use AAC. Multipoint connections are managed in the app.

Sennheiser
Battery and charging—700 mAh lithium-ion; up to 60 hours with noise cancelling on; full charge in about 2 hours; up to 4 hours from 5 minutes of charging; USB-C 5 V 800 mA

Sennheiser says the 60 hours was measured with an iPhone at medium volume; higher volume and aptX Adaptive can shorten it.

Sennheiser
Wired use—Hi-res digital audio over USB-C; 3.5 mm / 2.5 mm analogue cable

When listening over USB-C, the headphones decode digital audio internally; the analogue cable works even with a flat battery.

Sennheiser
Controls and app—Touch surface on the right cup; Smart Pause wear detection; Auto On/Off; 5-band equaliser and Sound Personalization in the Smart Control app

Smart Pause stops playback when the headphones are taken off and resumes when they are put back on; Auto On/Off shuts them down to save power when not in use.

Sennheiser
In the box—Carry case; USB-C charging cable; audio cable with 3.5 mm and 2.5 mm jacks; airplane adapter Sennheiser
Water resistance—No IP rating listed

With no certification against sweat or rain, care is needed when it gets wet during exercise.

Sennheiser