Sennheiser PXC 450

...the features according to the Sennheiser homepage if you are interested.

Features
Audiophile sound experience on the move: outstanding sound quality thanks to adaptive baffle damping and patented Duofol diaphragm technology
NoiseGard™ 2.0 active noise compensation provides best possible protection against ambient noise (up to 90.0%)
Comfortable fit and high level of passive ambient noise attenuation thanks to ...
...materials
TalkThrough function: for easy communication with the people around you while wearing the headphones
Volume can be adjusted directly on the headphones
Ideal for people on the move: comfortable, sturdy and foldable headphone design
Audio transmission always works - even in passive mode and without the batteries
Ideal for use with in-flight entertainment systems, MP3 players and all other portable and ... more

These are the first jumbo sized headphones that I have ever bought. Previously I have had to replace the in-ear headphones every 4 months. This is because I tend to listen to my music at a fairly high level, and after a short time, they begin to produce a hissing sound when the base is high.

However with these headphones I have been pleasently suprised. So far the sound quality has not changed. The music heard is incredibly clear, which means to fully appreciate the song you do not need to turn it up too high. Also if you are using these headphones with MP4's and watching movies, is when they really come into there own. They make it easy to get very involved in what your watching.

Also because of the soft padding around the ear piece, as well as the angle that they sit around your ears mean that you can wear them for a very long time.

Nevertheless there are some draw backs to having these headphones when you have to use them everyday. When you have to pack it up its a pain to make sure that they are not goin to get damaged. Also I dont like having to take a bag out with me, and with these headphones you really have to. Also I was not extremely impressed with the noise reduction. It did work to a certain extent, however I expected it to perform better when I was on the tube. With very loud noises the difference is not worth the money. However it does cut out the annoying sounds that you get every now and then with loud people or ironically, somebody else's music.

Anyway, these are the features according to the Sennheiser homepage if you are interested.

Features
Audiophile sound experience on the move: outstanding sound quality thanks to adaptive baffle damping and patented Duofol diaphragm technology
NoiseGard™ 2.0 active noise compensation provides best possible protection against ambient noise (up to 90.0%)
Comfortable fit and high level of passive ambient noise attenuation thanks to circumaural ear pads and padded headband made of top quality materials
TalkThrough function: for easy communication with the people around you while wearing the headphones
Volume can be adjusted directly on the headphones
Ideal for people on the move: comfortable, sturdy and foldable headphone design
Audio transmission always works - even in passive mode and without the batteries
Ideal for use with in-flight entertainment systems, MP3 players and all other portable and stationary audio equipment
Top quality materials and replaceable ear pads and cable for long service life
Comes with full accessories: transport case, 2 audio adaptors (in-flight entertainment and 6.3 mm), batteries
2-year warranty
Delivery Includes
PXC 450 high-end travel headphone
Transport Case
2 Audio Adapter (In-flight-Entertainment and 6,3 mm)
2 AAA batterys 

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