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SENNHEISER M3IETW2 True Wireless 2 Manual

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SENNHEISER M3IETW2 True Wireless 2 Manual

SENNHEISER momentum earphones Product imageImportant safety instructions

  • Read this instruction manual carefully and completely before using the product.
  • Always include this instruction manual when passing the product on to third parties.
  • Do not use the product if it is obviously defective or makes loud, unusual (whistling or beeping) noise.
  • Only use the product in environments where Bluetooth® wireless transmission is permitted.

Preventing damage to the product and malfunctions

  • Always keep the product dry and do not expose it to extreme temperatures (hairdryer, heater, extended exposure to sunlight, etc.) to avoid corrosion or deformation. The normal operating temperature is from 0 °C to 40 °C/32 °F to 104 °F.
  • To avoid loud, unusual (whistling or beeping) noise and to ensure proper noise cancellation, do not cover the microphone openings of the active noise cancellation circuitry located on the outside of the earbuds.
  • Use only attachments/accessories/spare parts supplied or recommended by Sennheiser.
  • Clean the product only with a soft, dry cloth.

If abused or misused, the rechargeable batteries may leak. In extreme cases, they may even present a risk of:

  • explosion,
  • fire development,
  • heat generation,
  • smoke or gas development.

Package contents

SENNHEISER momentum earphones FIG 1

Online you can find:

Product overview

Charging case M3IETW2 C

  • SENNHEISER momentum earphones FIG 2LED displays the charging process/charge status of the rechargeable battery of the charging case or of the earbuds (when inserted into the charging case)
  • Input for USB-C connector for charging the rechargeable batteries
  • LED button activates the LED display for 5 seconds
  • Built-in rechargeable battery for charging the earbuds on the go
  • Type plate
  • Charging compartment for the left earbud L
  • Magnetic holders
  • Charging compartment for the right earbud R
  • Charging contacts

Getting started

Waking up the earbuds and the charging case and charging the rechargeable batteries

SENNHEISER momentum earphones FIG 3Upon delivery, the rechargeable batteries of the earbuds and the charging case are in sleep mode and have to be woken up by connecting them to a power source once.

  • Insert the earbuds into the charging case.
  • Connect the USB-C cable to the charging case and to a USB power source (> 15). The earbuds and the charging case are woken up and the rechargeable batteries are being charged. The earbuds are now ready for use.


  • Press and hold the LED button on the charging case for 3 seconds.
  • The earbuds and the charging case are woken up and can now be used.

Using the earphones

Information on the rechargeable battery, the charging process and the first use. The earbuds and the charging case each have a built-in rechargeable battery. The charging case allows you to store the earbuds safely at all times while they are being charged.

Charging the rechargeable battery of the earbuds and the charging case

  1. SENNHEISER momentum earphones FIG 4Open the charging case by overcoming a slight magnetic resistance and insert the left earbud into the left charging compartment and the right earbud into the right charging compartment. The earbuds are magnetically pulled into the charging compartments.
  2. Connect the USB-C connector of the USB cable to the USB- C socket of the charging case.
  3. Connect the USB-A connector to a corresponding socket of a USB power source (to be ordered separately). Make sure that the USB power source is connected to the power supply system.
  4. The rechargeable batteries of the earbuds and the charging case are being charged.


Charging case WITH earbuds inserted Charging case WITHOUT earbuds inserted
pulses yellow … earbuds and charging case are being charged … charging case is being charged
lights up green … earbuds and charging case are fully charged … charging case is fully charged




flashes red

… a charging error/ battery error has been detected in at least one earbud (> 34) … a charging error/ battery error has been detected in the charging case (> 34)


Care and maintenance of the earbuds/charging case

Liquids can damage the electronics of the product! Liquids entering the housing of the product can cause a short-circuit and damage the electronics.

  • Keep all liquids far away from the product.
  • Do not use any solvents or cleansing agents.
  • Only clean the charging case with a soft, dry cloth.
  • Clean the earbuds with a slightly damp cloth.
  • Clean the charging contacts on the earbuds and in the charging case from time to time using e.g. a cotton swab.

Information on the built-in rechargeable battery

Sennheiser ensures and guarantees that the rechargeable battery performs at its optimum upon purchase of the product. If, upon purchase or within the warranty period, you suspect that the recharge-able battery is obviously defective or if a charging error/battery error is displayed (> 8), stop using the product, disconnect it from the power supply system and contact your Sennheiser partner. Your Sennheiser partner will coordinate the repair/replacement with you. Do not return a product with a defective battery to your dealer or Sennheiser partner unless requested to do so. To find a Sennheiser partner in your country, search at

FAQ/If a problem occurs …

Current list of frequently asked questions (FAQ) Visit the MOMENTUM True Wireless 2 product page at  There you will find a current list of frequently asked questions (FAQ) and suggested solutions. f you, and therefore the earphones, leave the Bluetooth transmission range of the smartphone, the sound quality deteriorates increasingly until you hear the voice prompt “No connection” and the connection breaks down completely. If you immediately re-enter the Bluetooth transmission range, the connection is automatically reestablished and you hear the voice prompt “Connected”. If this is not the case, tap the touch control panel of the earbud 1x.

Your question has not been answered or the problem persists?

If a problem occurs that is not listed in the FAQ section or if the problem cannot be solved with the proposed solutions, please contact your Sennheiser partner for assistance. To find a Sennheiser partner in your country, search at > “Service & Support”.

Leaving the Bluetooth transmission range

Wireless calling and streaming are only possible in the Bluetooth transmission range of your smartphone. The transmission range largely depends on environmental conditions such as wall thickness, wall composition etc. With a free line of sight, the transmission range of most smartphones and Bluetooth devices is up to 10 meters.


MOMENTUM True Wireless 2 M3IETW2

Wearing style… True wireless stereo earphones
Ear coupling… ear-canal
Frequency response… 5 Hz to 21 kHz
Transducer principle… dynamic, closed-back
Transducer size… 7 mm
Sound pressure level (SPL)… 107 dB (1 kHz/1 MW)
THD (1 kHz, 94 dB SPL)… < 0.08 %
Active noise cancellation ANC… 1 microphone per earbud
Microphone principle… MEMS
Microphone frequency response… 100 Hz to 10 kHz
Microphone pick-up pattern speech and ANC)… 2-mic beamforming array

Manufacturer Declarations


Sennheiser electronic GmbH & Co. KG gives a warranty of 24 months on this product. For the current warranty conditions, please visit our website at or contact your Sennheiser partner.

In compliance with the following requirements

  • General Product Safety Directive (2001/95/EC)
  • Compliant to Sound Pressure Limits according to country-specific requirements

Notes on disposal

  • Battery Directive (2006/66/EC & 2013/56/EU)
  • WEEE Directive (2012/19/EU)

The symbol of the crossed-out wheeled bin on the product, the battery/rechargeable battery (if applicable) and/or the packaging indicates that these products must not be disposed of with normal household waste, but must be disposed of separately at the end of their operational lifetime. For packaging disposal, please observe the legal regulations on waste segregation applicable in your country. Further information on the recycling of theses products can be obtained from your municipal administration, from the municipal col-lection points, or from your Sennheiser partner.


Sennheiser is a registered trade mark of Sennheiser electronic GmbH & Co. KG. Apple and the Apple logo are trademarks of Apple Inc., registered in the U.S. and other countries. App Store is a service mark of Apple Google Play and the Google Play logo are trademarks of Google LLC. The Bluetooth® word mark and logos are registered trademarks owned by Bluetooth SIG, Inc. and any use of such marks by Sennheiser electronic GmbH & Co. KG is under license.




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