I like that they also do not make an noise
926547
Keep our pillows clean with giving us that extra barrier. I like that they also do not make an noise.
217420
I am not an audiophile. That said, I have no complaints. The sound is fine and they are comfortable to wear. Worth the money. Just one thing - I don't think these are noise-reducing.
4733968
These work well. This is a rural area with little electrical noise.
2086379
One didn't make any noise whatsoever, the other one barely emitted a high-pitch bleep of some kind. Cute and cuddly, though my two fifteen-year-olds were uninterested.
1868756
I wish they weren't just 1,200 RPM, but they are only 3pin. They easily move air in and out, and you can't even hear them if there is ANY noise in the same room.
2952558
I really like this product and it works for me. There is a little noise but it does not bother me at all.
3539086
They are perfect for my little kids because the sound doesn't go up very high so they aren't hurting their ears. These are comfortable to wear and fit good. My kids don't hear all the background noise and I don't hear their music.
3785300
I bought 4 units of these air purifiers and have been using them in each of my bathrooms for about a month now. (I had to return one of the units for replacement because the UV light is not working.)  I do notice that the air feels cleaner and fresher, and the bathroom odor doesn't seem to linger.  I just don't like the noise level it emits which sounded like the ceiling fan is always on.  But since they are installed in my bathroom and don't hear it 24/7, I don't mind the noise.
4648038
They really do cancel out all noises. I wore them at work one day and couldn't even hear my desk phone ring. I regularly wear them while mowing the grass. They work great and I don't have to crank the volume way up just to hear the music.
3240845
I bought my first set of these ear buds while in the airport during a layover when the old ear buds I had with me failed. The clerk sold them to me on the fact that there was no plastic so they were "green". I hoped that the lack of plastic would mean that I wouldn't hear the sound of the cable rubbing against my clothes when I go for my walks. I was right -- it reduces that noise greatly. Also, I had dropped them in water and had to wait while the new set arrived so I bought a cheaper pair of Sony's -- huge difference. When I used the cheaper pair I had to turn the volume up by 5-6 bars, in comparison to the one bar that I use with these. Strong sound. I also like the thread colors on the cord.
3020547
Comfortable, medium-weight headphones sound good, whether or not they are switched "on." When they're "on," they reduce a decent amount of the background noise. They don't cancel noise, but they do make things quieter. I like that they take AAA batteries; it's easy to find rechargeables and one battery will last most of a workweek at the office. I also like that, with or without batteries, these work as regular headphones.

When switched on, there is a very soft (very soft) wooosssh noise. I notice it only when there is no music playing and I have the noise cancellation turned on in an already quiet room. If you're a true audiophile, then it might bother you. But a true audiophile wouldn't listen to music in a noisy room anyway, right?

Air conditioner/ hard drive noise = gone
My own keystrokes as I type this review = gone (which is a little creepy)
Conversations down the hall = reduced
Conversations in the next cube = still there, not reduced
Person talking to you = still there, not reduced
835662
Yes they are noisy, but they stop really good and have very little fade after a long day of driving fast or competitive driving.
539517
They do not swing upside down as bad as others have voiced. I like their lightness and so far no pressure spots on my feet.
903899
Works as intended, very little noise on a level surface.
1506755
These do not get loud at all. There is a loud white noise when they are dormant. They looks cool. Yeah thats the only positive
4205330
They are quiet and move a decent amount of air, the only sound I can hear when they are in my case is air hitting the heatsink. The only weird thing is that they don't seem to change RPM even when plugged in to the CPU fan header but they move enough air that I am not worried.
3701942
We have two pairs of these in the car so the kids can watch movies on long drives.  I like that they do not have a volume adjustment on the headphones, so my 4-year-old can't turn the sound up too loud.  We have had them for a year and a half and other than my son taking off the padded part every now and then, they are perfect.