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
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,
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
- SPL (1 kHz/1 Volt): 107 dB
- THD (1 kHz): < 0.1%
- Connectors: 3.5mm, 3.5mm double mono plug in-flight
- Weight: 3.7 ounces (105 grams)
- 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
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