Summary: I bought a pair of PXC 450's when they first came out. I travel a lot for work, and I wanted the very best NC headphones I could get, since I have never been able to like IEM's from a comfort perspective.
Pros: The best sounding NC headphone I have heard; also sounds good with the NC off
Cons: positioning on the head critical to having the NC work well
Summary: Brilliant set of noise-cancelling cans, complete with sound quality at an audiophile-grade level. Although still functional without batteries, sound quality loses its spark when they're taken away.
Pros: Sound quality; noise cancelling; leak-free even at high volume; great build quality; price; lightweight.
Cons: No 'TalkThrough' feature as seen on PXC 450s; less inspiring sound without batteries.
Conclusion: Overall, the Sennheiser PXC 350 headphones have done themselves proud once again and, with them going for Â£149.95 at Play.com there’s really no reason why you shouldn’t pick a pair up, if you’ve been eyeing them for a while.
Excerpt: Back in October the Sennheiser PXC 450 were rated the best noise canceling headphone on the market, in november a black edition was released dubbed the PXC 350 and retailing for some Â£70 less.
Excerpt: Sennheiser's active noise-cancelling PXC 350s fit snugly around the ear. This helps reduce background noise, even without the noise-cancelling circuit engaged. Turn it on, however, and the din of air conditioning and engine noise retreats into the distance, replaced only by a slight hiss.