Like Sony's in-ear MDR-NC22 noise-canceling earphones, the new MDR-NC40's best feature is its price: Both pairs are only $100. The MDR-NC40 isn't an in-ear model but a supra-aural set of headphones, meaning that they sit on the ears without creating a seal.

Affordable; Compact, collapsible design; Decent noise cancellation; Enjoyable audio performance with solid bass performance

Takes a standard AAA battery instead of a rechargeable cell; Battery pack is in the middle of the headphone cable

No, I would not recommend this to a friend

Comfortable; Lightweight

Poor Sound

These comfortable cups won't stay on when exercising. Instead, they're designed for long journeys. With the noise-cancelling feature turned on outside noise is blocked well, but the delivery suffers from woolly bass and unexciting treble. With it turned off they sound relatively lifeless.

Noise-cancelling works well

Woolly bass and unexciting treble; Lifeless sound when noise-cancelling is turned off

These headphones are great and as far as I can tell are equal to the "high price brand". Great sound and comfortable to wear. The "high price brand" also cost about 5 times more than these.

Comfortable; Compact; Good Bass; Lightweight; Rich Sound

Somehow, the Ballad of Jed Clampett comes to mind, as I start to write this. You know, the Beverly Hillbillies. He was living his life, struck gold, and everything changed. That's kind of what happened here. Except I didn't strike gold or become rich. Yeah, the metaphor doesn't exactly work.

Very light; portable; built in EQ/NC function

Expensive for what they are; require a battery

----Update 06/24/09----------Still going strong. These suckers have survived MANY cross-countr

Sound; NC; convenience; price; accessories; and light weight

Don't fold completely flat; rely heavily on NC function; a little overboosted

These headphones do the job and exceed my expectations. Insane bass that you can hear that subwoofers can't produce. My friend would be talking and pointing gestures at me and I would not know what the language is. Probably the best headphones and doesn't even weigh a pound it feels like.

I prefer on-ear headphones. These headphones feel just a little tight on my head which is probably good for keeping them on while riding the commuter train. There is almost no sound 'bleed', when I have them of my ears, around my neck I can not hear the music.

I purchased the Sony MDR-NC40 headphones almost on impulse because the price was really unbeatable, plus I knew I had a trip coming up to test these out on. These ultra-light noise-cancelling headphones retail for $100, and claim to reduce up to 90% of noise.

These are a pair of noise-canceling headphones from Sony. With the power of one AAA battery, they can cancel ambient noise. The way they do this is with a tiny microphone on the outside of the headphones, which records the sounds that are heard, and then plays them back at a 180 degree angle, which...