Pros I'd like to say something positive, but cannot.
Cons The noise cancelling feature is wholly ineffective.
It is advertised as up to 80% effective...while in America - I guess you could say I could only hear 80 percent of all noise on the entire planet.
Summary These will be worth the cost when the price drops to two dollars with free shipping included.
Pros Ear buds work OK, unit is relatively light even with the battery
Cons I would have to agree with most of the other reviewers in that I could not discern any active noise reduction at all. Sound quality is a bit tinny, but since I mostly use my MP3 for podcasts, that is OK.
Summary I had hoped to use these at the health club on the treadmills to reduce the background noise. I agree with one of the other reviewers that they just won't work in that kind of environment. These may work acceptably in other environments, say, in an airplane, but for the purpose I had intended, they just do not fit the bill. I have tried a friend's Bose noise reducing head phones and they work very acceptably. I was hoping that although these might not be expected to produce the same results as the much higher priced Bose, they would provide at least a moderate degree of active noise reduction. Unfortunately that is not the case. I really do wonder if I just got a defective product--I just simply am unable to detect any noise reduction at all in any environment that I have tried.
Pros The rubber ear pads are nice. They fit comfortably, and they offer s o m e - but not much - passive noise cancelling
Cons Unacceptable low sound quality - which is atypical for JVC products - and no discernable a c t i v e noise cancelling at all.
Summary The sound of the music is seriously lacking in volume, particularly in the lower, bass frequencies. I have compared this unit with the regular earphones that came with my inexpensive mp3 player from Radio Shack ($14 for mp3 player INCLUDING the earphones), and the JVC HA-NCX77 does not even come close.
I have tried using the JVC HA-NCX77 with soft - and with loud background noise in several different frequency ranges, and there is no active noise cancellation noticable. I have bought many other JVC products for many years. I was usually satisfied, and I bought these earphones largely because they came from JVC. Unfortunately, I must return them to the seller, because they are not useful, and I would not recommend them to anyone.
Pros It has a case
Cons No Noise Cancellation
Summary The overall sound quality is tinny. When the switch for the noise cancellation is turned on there is no decernable difference. The free headsets I get at tradeshows are better sound.
Pros Unfortunately, I could not find any redeeming features to warrant purchasing these headphones
Cons The noise cancelling feature is mediocre to non-existant. The earbuds do not stay in place in the ear canal, and the sound quality is muted and does not give the full range of sound.
Summary If you buy these you will be very disappointed in several aspects from sound quality to noise suppression. You must also be very still in order to keep the earbuds in place and will have to constantly readjust the positioning.