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Sennheiser MM 550-X

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

4 Reviews

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Item # 143MM550X

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Our take on the Sennheiser MM 550-X

The Sennheiser MM 550-X portable headphones give you the best of all worlds — superb stereo sound, wireless convenience, and luxurious comfort. They're fantastic for enjoying your music and managing your phone calls without wires or outside distractions.

A roadworthy headset that does it all

The Sennheiser MM 550-X portable headphones give you the best of all worlds — superb stereo sound, wireless convenience, and luxurious comfort. They're fantastic for enjoying your music and managing your phone calls without wires or outside distractions.

Sennheiser's built-in active noise-canceling circuitry quiets the environment around you, while Bluetooth technology lets you make 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 on the right earcup for convenient operation while your phone or music player remains safely in your pocket, purse, or backpack. Plus, the MM 550-X headphones support the latest aptX technology — a sophisticated audio circuit that delivers true high-fidelity stereo sound wirelessly over Bluetooth with aptX-enabled sources.

Noise-canceling technology gives you peace and quiet

Sennheiser's NoiseGard™ 2.0 technology reduces extraneous sounds by up to 90%, such as engine roar, wind noise, and the conversation of surrounding passengers. Tiny microphones in the headphones pick up the sounds of your environment. Advanced circuitry then creates a signal that "cancels out" much of this external noise without affecting your music or phone calls. A handy "TalkThrough" function lets you temporarily override the noise-canceling circuit with the push of a button to carry on a conversation with a seatmate or give your drink order to the flight attendant.

Exceptional comfort, sound quality, and convenience

The MM 550-X's earcups feature plush leatherette cushions that feel great. Their around-the-ear design helps further seal out distracting noise while taking pressure off your ears. An adjustable padded headband ensures comfortable listening for hours on end, making these 'phones ideal for long trips. The headband conveniently folds up for easy storage when you travel. Sennheiser's patented Duofol™ diaphragms deliver detailed, crystal clear sound, while selectable SRS WOW HD™ audio technology lets you add more spaciousness and low-frequency punch to your movies, games and music. And just in case you need it, Sennheiser includes a cable plus an airline adapter for a direct wired connection in situations where Bluetooth is not permitted, or you want to make use of in-seat entertainment and other wired sound sources.

Product Highlights:

  • portable, folding, around-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
  • NoiseGard 2.0 noise-cancellation technology provides up to 90% active noise cancellation
  • TalkThrough function — lets you pause the noise-canceling for brief conversations
  • SRS WOW HD™ technology for added spaciousness and stronger bass
  • advanced DuoFol™ drivers for detailed sound and extended frequency response
  • rechargeable lithium-polymer battery included
  • single battery charge gives you:
    • up to 20 hours talk time without NoiseGard
    • up to 10 hours listening time without NoiseGard
    • up to 8 hours listening time with NoiseGard
  • advanced Duofol™ drivers with neodymium magnets
  • integrated controls on the right earcup include track, volume, and answer/end call functions
  • frequency response 15-22,000 Hz
  • 60" detachable audio cable with stereo mini plug
  • airline adapter, full-size headphone adapter, USB charging cable, multi-country wall charging adapter, and carrying case included
  • weight: 6.31 oz.
  • warranty: 2 years
  • Our 60-day money-back guarantee

What's in the Box:

  • MM 550-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
  • 3.5mm-to-1/4" 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

Featured Video:


Sennheiser MM 550-X Reviews

Average Customer Review(s):

(4 Reviews)

A sports car with one gear

rennam from Central Ohio on 1/10/2013

Crutchfield Customer Review (What's this?)

These headphones are high quality in every respect. However, imagine having a nice car and you like to lean on it every now and then. Press the gas a little through a turn. Feel the suspension keep the car on the road nice and tight. Now, imagine that car only has one gear. Its got all the potential, but just cant do it. So frustrating. The volume on these headphones is way to low at their peak volume. I ignored the other reviews I read elsewhere figuring it couldnt be that bad, well, I may return these things. Its that bad. Too bad, because everything else about these headphones is well worth the money. The low volume is the reason for the low rating.

Pros: The performance of all of its features met or exceeded expectations.

Cons: Sound volume... too low.

Pricey but worth it

DonInDallas from Dallas, TX on 10/22/2012

Crutchfield Customer Review (What's this?)

I am planning on taking these with me to Europe next month and tried them out and I am very pleased with the weight and quality. The sound is crisp and clear, and what I really like is that when you have them on, other people don't hear them and I don't hear them either. I would definitely recommend.

Pros: Light weight. Bothe corded and wireless.

Cons: Price.

Not that great

Anonymous from Madison WI on 9/6/2012

Crutchfield Customer Review (What's this?)

I purchased these hoping they would replace my 10 year old Bose QC2 headphones. I figured the steep asking price would be justified by Sennheiser's legendary sound quality. Unfortunately, there were too many design trade-offs made with these phones: 1. Noise cancellation wasn't very good - it just killed the sound quality. 2. Sound quality was not noticeably better than my iPhone buds. It was worse once you turned on the active cancellation. 3. The cans were too small for my ears. I don't think my ears are all that big, but after a couple of hours, I had to take them off due to discomfort. 4. Cranked, they weren't all that loud. I tried to make them work for me, but after 2 weeks returned them for a new Bose NC headset.

Pros: Wireless, Bluetooth control

Cons: Can't crank em up, noise cancellation is poor, complicated controls

MX 550-X

Jackson from Afghanistan on 4/23/2012

Crutchfield Customer Review (What's this?)

Very good headphones. I get about 8 hours of non-stop run time. Works well with my 2011 Mac Book Pro.

Pros: Comfortable and light. Great sound. Bluetooth so no wires. 8+ hours run time. The rechargable battery comes out easy, so you could keep a spare and swap out very quickly.

Cons: Pricey


Hands-on research

Features and Specs

Fit Style Over-the-ear
Earcup Type Closed
Earcup Width x Height 2.922" x 3.288"
Noise-canceling No
Bluetooth Yes
Mic For Taking Calls Yes
iPhone Control ---
Lightning Connector No
Android Control ---
Frequency Response 15-22k Hz
Sensitivity 107 dB
Impedance 100/590act Ohms
Weight 6.31 ounces
Cord Length 60"
1/4-inch Adapter Included Yes
Volume Control Yes
Parts Warranty 2 Years
Labor Warranty 2 Years

Product Research


Overview: The Sennheiser MM 550-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 550-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 550-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 550-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 550-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. The following 3rd party devices / configurations have built-in apt-X support (as of 7/18/2012):

  • Apple Mac OS X Snow Leopard and Lion Operating Systems
  • Apple Mac Mini (latest generation with latest OS update)
  • Apple Macbook Air (latest generation with latest OS update)
  • Apple Macbook (latest generation with latest OS update)
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  • HTC One X
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  • Samsung Galaxy Tablet 7.0 Plus
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NoiseGard 2.0 Noise Cancellation: NoiseGard technology is an active noise compensation system, originally developed for use by pilots. NoiseGard uses tiny microphones to measure ambient noise (up to 1 kHz) near the ears. The phase of the noise is then inverted (180° out of phase) and added to the original noise, reducing background noise by up to 23 dB (90%). NoiseGard can be used with Bluetooth wireless reception or when the MM 550-Xs are wired; NoiseGard can also be turned off when not needed.

TalkThrough: The TalkThrough function allows you to have a conversation with the person next to you without taking the headphones off. When TalkThrough is activated, microphones mounted on the outside of the headphones pick up sound in the immediate vicinity and background noise is filtered out (the music is also turned off).

SRS WOW HD: SRS WOW HD improves the dynamic audio performance of compressed and uncompressed audio by expanding the size of the audio image and creating a deep, rich bass response. SRS WOW HD widens the horizontal sound field and raises the vertical sound image to retrieve audio information lost in the mixing process. Using sculpted filters and driver physics, SRS WOW HD goes beyond the low-frequency limitations of speakers and headphones to maximize the bass response. In addition, SRS WOW HD provides high-definition control for better clarity, and center control for dynamic extraction and positioning of the main content.

Earcups: The MM 550-X features a comfortable, over-the-ear design that let you enjoy long listening sessions while on the move. The closed design helps to provide superb passive noise attenuation. The fully-adjustable headband allows you to find the perfect fit.

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 550-X has a removable BA 370 PX Lithium-Polymer battery pack (3.7 volts DC/1 Wh) which provides up to 8 hours playback using Bluetooth reception and NoiseGard, up to 10 hours playback using Bluetooth without NoiseGard, and up to 20 hours using just NoiseGard (with Bluetooth turned off). 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 550-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. A 3.5mm-to-1/4" adapter, and an in-flight audio adapter (dual mono 3.5mm) are included for added convenience.

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

Specifications: The MM 550-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-to-1/4" adapter, 3.5mm double mono plug in-flight adapter
  • Weight: 6.31 ounces (179 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

Our Product Research Team

At Crutchfield, you'll get detailed, accurate information that's hard to find elsewhere. That's because we have our own in-house Product Research team. They verify what’s in the box, check the owner's manual, and record dimensions, features and specs. We stay on top of new products and technologies to help people make informed choices.