Chat
Contact us
Close contact box
Connect ID #
590 520 435 3
Connect ID #
590 520 435 3
All finished with your chat session?

We’ll email you a transcript of this conversation for your records.

All of our representatives are
currently chatting with other customers.

Please enter your name.  
Please enter a valid email address. Why is this required?
Please enter your US phone number.  

For Tech Support, call 1-888-292-2575

Thank you, !
Our conversation will be emailed to

Your Advisor,

More about me
Please enter a question  
Don't wait on hold. We'll call you back when it's your turn to talk with the next available .
Please enter your name  
Please enter your phone number  

Please enter a message  

Calls may be recorded for training and quality control purposes.

We are located in Virginia USA.

Sennheiser MM 400-X

Bluetooth® stereo headset with aptX® high-fidelity wireless audio capability

Item # 143MM400X

Going somewhere? Don't forget your Sennheiser MM 400-X portable headphones.

Going somewhere? Don't forget your Sennheiser MM 400-X portable headphones.

Discontinued item
2 questions - 4 answers

Item # 143MM400X

About the Sennheiser MM 400-X

Bluetooth for wireless music and talk

Going somewhere? Don't forget your Sennheiser MM 400-X portable headphones. They're fantastic for enjoying your music and managing your phone calls without getting tangled up in cords. These headphones include built-in Bluetooth technology for a hassle-free wireless connection to compatible devices, such as many cell phones, laptop computers, tablets, and MP3 players. You can use the integrated volume, track skip, and call answer/end buttons built into the right earcup for convenient operation while your phone or music player remains safely in your pocket, purse, or backpack. The MM 400-X headphones even support the latest aptX technology — a sophisticated audio circuit that delivers true high-fidelity stereo sound wirelessly over Bluetooth with aptX-enabled sources.

Bluetooth for wireless music and talk

Going somewhere? Don't forget your Sennheiser MM 400-X portable headphones. They're fantastic for enjoying your music and managing your phone calls without getting tangled up in cords. These headphones include built-in Bluetooth technology for a hassle-free wireless connection to compatible devices, such as many cell phones, laptop computers, tablets, and MP3 players. You can use the integrated volume, track skip, and call answer/end buttons built into the right earcup for convenient operation while your phone or music player remains safely in your pocket, purse, or backpack. The MM 400-X headphones even support the latest aptX technology — a sophisticated audio circuit that delivers true high-fidelity stereo sound wirelessly over Bluetooth with aptX-enabled sources.

Great comfort, sound, and convenience

The MM 400-X's soft padded ear cushions and adjustable headband provide a comfortable fit for hours of relaxed listening, making these 'phones great to have on long trips. The headset's folding design makes for easy storage when you travel. Sennheiser's patented Duofol™ diaphragms provide detailed, crystal clear sound. And just in case you need it, Sennheiser includes a cable plus an airline adapter for a direct wired connection in situations where Bluetooth isn't permitted, or you want to make use of in-seat entertainment and other wired sound sources.

READ LESS

Product highlights:

  • portable, folding, on-the-ear design
  • padded, closed earcups and adjustable headband
  • Bluetooth® wireless operation with advanced aptX audio circuitry for streaming high-quality stereo sound from aptX-enabled devices
  • built-in microphone and wireless earcup controls for hands-free conversations using compatible Bluetooth cell phones
  • integrated controls on the right earcup for track, volume, and answer/end call functions
  • rechargeable lithium-polymer battery included
  • single battery charge gives you:
    • up to 20 hours Bluetooth talk time
    • up to 10 hours Bluetooth listening time
  • advanced Duofol™ drivers for outstanding sound quality
  • frequency response 15-22,000 Hz
  • 60" detachable audio cable with stereo mini plug included for wired listening options
  • airline adapter, USB charging cable, multi-country wall charging adapter, and carrying case included
  • weight: 3.7 oz.
  • warranty: 2 years
  • Our 60-day money-back guarantee
  • MFR # 504511

What's in the box:

  • MM 400-X Wireless headphones
  • BA 370 PX Lithium-Polymer rechargeable battery pack (installed)
  • Wall charging power supply
  • US power plug adapter
  • EU power plug adapter
  • UK power plug adapter
  • AU power plug adapter
  • Airline adapter (single female 3.5mm-to-dual male 3.5mm)
  • 50" USB charging cable (Type A USB on one end and proprietary USB on the other end)
  • 5' Audio cable (male 3.5mm miniplug on one end and male 2.5mm sub-miniplug on the other end)
  • Zippered storage pouch
  • Instruction Manual on CD-ROM
  • Quick Guide
  • Safety Guide
  • Compliance statement
  • "Replacement of the Mains Unit" sheet

Featured video:

Customer reviews

Loading reviews...

Sennheiser MM 400-X reviews

Average review:

2 reviews

Thanks for submitting your review

Filter by rating

Customer photos

Sort reviews

Sort by:
Items per page:
View page:

Verified customer (What's this?)
Verified employee purchase (What's this?)

Pros:

Cons:

Crutchfield response

<< >>

More details on the Sennheiser MM 400-X

Mark G.

Features & specs

General
Fit Style On-ear
Earcup Type Closed
Earcup Width x Height 2.275" x 2.255"
Noise-canceling No
Bluetooth Yes
Bluetooth Version ---
Single-earbud Operation ---
Mic For Taking Calls Yes
Voice Assistant Access
Amazon Alexa No
Google Assistant No
Siri No
Connectors
3.5mm No
1/4" No
Lightning No
4.4mm balanced No
XLR4 balanced No
2.5mm No
Other None
Specs
Frequency Response 15-22k Hz
Sensitivity 107 dB
Impedance N/A
Weight 3.7 ounces
Cord Length 60"
Parts Warranty 2 Years
Labor Warranty 2 Years
The Sennheiser MM 400-X replaces these items:

Product Research

Features

Overview: The Sennheiser MM 400-X headphones are an accessory that allows you to enjoy your digital music files on your mobile phone or portable music device, including those equipped with Bluetooth technology. The MM 400-X can be used wirelessly, or in places where Bluetooth isn't available, you can plug them in and use them as wired headphones.

Bluetooth Wireless Reception/Transmission: The MM 400-X features Bluetooth v2.1 wireless reception and transmission with a built-in microphone for cable-free use with select Bluetooth enabled phones and audio devices. Supported Bluetooth profiles include A2DP (Advanced Audio Distribution Profile), AVRCP (Audio/Video Remote Control Profile), HSP (HeadSet Profile), and HFP (Hands-Free Profile). The MM 400-X saves the connection profiles of the last eight devices with which it was paired; when turned on it automatically tries to connect with one of those devices.

Note: Not all Bluetooth enabled audio devices will be compatible.

apt-X: The MM 400-X headphones are equipped with apt-X, an audio coding technology that works within Bluetooth to wirelessly deliver CD-quality audio from your portable music device to the headphones. With apt-X, you can listen to your digital music files in crisp, pure, and full stereo sound.

Controls: On the right ear-cup there are integrated controls for your connected phone or audio device. Audio controls include volume, skip forward or backward, fast forward or rewind within a song, play, and stop. Phone controls include volume, accept call, reject call, end call, redial, voice dial, and mute.

Note: All control functions must also be supported by the connected device.

Battery Pack: The MM 400-X has a removable BA 370 PX Lithium-Polymer battery pack (3.7 volts DC/1 Wh) which provides up to 10 hours playback using Bluetooth reception. A power supply with US, UK, European, and Australian plug adapters is included to charge the battery pack; charging time is approximately three hours. The headphones can also be charged using a computer's USB port.

Collapsible Design: These headphones feature a collapsible design with metal-reinforced headband to ensure portability and durability.

Cord & Adapter: The MM 400-X will also work as wired headphones, useful when Bluetooth connection is not an option. The headphones come with a 60" mini-jack cable terminated by a 3.5mm connector for a wired connection. An in-flight audio adapter (dual mono 3.5mm) is included for added convenience.

Carrying Case: A nylon carrying case is included to protect the headphones during storage or transport.

Specifications: The MM 400-X has the following specs:

  • Frequency Response: 15-22kHz
  • Nominal Impedance: 590 Ω active mode; 100 Ω passive
  • SPL (1 kHz/1 Volt): 107 dB
  • THD (1 kHz): < 0.1%
  • Connectors: 3.5mm, 3.5mm double mono plug in-flight adapter
  • Weight: 3.7 ounces (105 grams)
  • Bluetooth:
    • Version: 2.1 + EDR
    • Range: up to 33' (10 meters)
    • Transmission Frequency: 2.4 GHz
    • Transmission Power: 8 dBm
    • Profiles: HSP, HFP, A2DP, AVRCP
    • Codec: SBC, apt-X

Loading accessories...

Customer Q&A

2 questions already asked

Q
I have an iPhone 4 can I use these headphones straight out the box or do I need a dongle for the Aptx ?
[ TimChad  Apr 07, 2014 ]
3 answers
A
Hi Tim C, Please check on this but as far as I know the iPhone does not support AptX. The Mac OS does and I believe Windows does too, but I believe the iPhone does not. One thing you might want to know about these headphones is that they have a crystal clear high and mid range but very poor low range. I ended up returning them and trading them for the Dr Dre BT headphones, which are more expensive and don't have as clear of a high range but they have a significantly much better bass response.
[ Alex  Apr 08, 2014 ]
A
They were a gift and my daughter says they work great
[ Fred  Apr 08, 2014 ]
A
You should be good to go!! As long as you have Bluetooth
[ Fred  Apr 08, 2014 ]
Q
Does this only work with Bluetooth? or is there a wired option as well?
[ seth  Dec 13, 2013 ]
1 answer
A
The MM 400-X can be used wirelessly, or in places where Bluetooth isn't available, you can plug them in and use them as wired headphones.
[ Jeff  Dec 13, 2013 ]  Staff

Loading articles...

TOP