Audio-Technica's ATH-ANC3 headphones, the third in our review series (after the Etymotic hf2 and Ultimate Ears super.fi5), were the first I encountered with active noise canceling. Active noise canceling (ANC) headphones produce an inverted sound wave based on exterior sounds. While the hf2 and super.fi5 create a seal around the audio canal to tone down the outside world, the ATH-ANC3 attacks the situation head-on.It has a little unit on its cord, with a power switch for the noise canceling, and a monitor button that turns the ANC off. The noise-canceling sound wave results in hiss when no music is playing. Audio is amplified, so that sounds are more powerful at low levels. The ATH-ANC3's noise canceling is terrific. On a commuter jet, these headphones were much more assertive at shutting out the plane's 87 db white noise than several noise isolating models. I'm typing this three feet from an in-window air conditioner, and I can barely hear the compressor or fan, while my music is powerful and clear. The headphones also did a pretty good job in the office, where conversations and abrupt noises were more prevalent. Coupled with the audio amplification, they were almost universally effective. The same can be said for the ATH-ANC3's overall sound: they're wonderfully balanced, satisfying headphones for a wide spectrum of music. Sounds across the spectrum were crisp and clean, with a good balance of low-end oomph and general richness. I didn't find a single song that didn't sound good through them, even a 56 kbps mp3 recorded off an old vinyl 45. Performance is equally good at low and high volumes. Wind is the ATH-ANC3's Achilles' heel. I found it next to impossible to wear these headphones on my bicycle. As best I could tell, the microphone that processes the external noise had trouble understanding the variable wind and ended up amplifying rather than canceling it. I couldn't hear my low-volume music, and the wind noise actually felt louder than if my ears were bare. With the ANC turned off, the headphones lost a lot of their dynamic range, diminishing their performance. They're best used with the ANC on. The Audio-Technica ATH-ANC3 active noise canceling headphones come with an extra cord segment, rubber earbuds in three sizes, an airplane seat adapter jack, and a large, four-pocketed hard case. They're very comfortable and don't create fatigue over time. Which is an extra perk, since they're perfect for long-haul flights. Highly recommended for travelers, and anyone who likes to get great sound that overcomes noisy environments.