"Sleigh bells ring, are you list’nin’?” “Strike the harp and join the chorus!” “What a bright time, it’s the right time, to rock the night away!” “Yuletide carols being sung by a choir,” “Just hear those sleigh bells jingling, ring-ting-tingling, too!” “Shall I play for you, pa-rum-pum-pum-pum, on my drum?” “The cattle are lowing — the poor baby wakes.” Well, of course the poor baby wakes; who could sleep with all that racket? The holidays aren’t just festive — apparently, they’re positively deafening. Maybe that’s why companies like Bose are hoping that ’tis the season for some good noise-canceling headphones. O.K., that’s a cheap joke. Noise-canceling headphones do not, in fact, do anything about general cacophony like tingling sleigh bells, striking harpists and lowing cattle. I mean, any headphones minimize those kinds of unpredictable sounds to a certain extent, simply because they’re covering up your ears. But true noise-canceling headphones are made to reduce steady sounds like airplane engine roar, car road noise and train rumble. These headphones involve “a microphone, placed near the ear, and electronic circuitry that generates an ‘antinoise’ sound wave with the opposite polarity of the sound wave arriving at the microphone. This results in destructive interference, which cancels out the noise within the enclosed volume of the headphone.” (Well put, anonymous Wikipedia contributor!) Bose-type headphones are great at eliminating low-frequency roar, but eliminating higher-pitched sounds is a much more challenging technological task. In consumer headphones, those sounds are primarily blocked by the earcup itself, making the design of its seal rather critical. Once you have noise-canceling headphones, you can listen to music or videos on the train or plane at a much lower (and safer) volume level. You avoid “noise fatigue,” a tiredness and edginess that supposedly arises from long hours of exposure to loud noise. And, of course, you strike your fellow passengers as a savvy, experienced hard-hitter who knows all the tricks in the travel game. Bose has led the industry for years, lately with two headphone models: the QuietComfort 2 (AAA battery, complete ear enclosure) and the QuietComfort 3 (rechargeable battery, slightly more compact because they sit on your ears instead of surrounding them). Well, if your sales are getting eaten alive by cheaper rivals, and you don’t want to play the price game, you have only one option: play leapfrog. Make your gadget so much better than the me-toos that people will be willing to pay your premium once again. That’s the idea behind Bose’s new QuietComfort 15 model, which replaces the QuietComfort 2. (Whatever became of the QuietComfort 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 and 14, anyway?) Bose has added a second set of microphones on the inside of the earcups, redesigned the earcup seal and further refined the audio circuitry. Bose says that the results are immediately obvious: much, much better noise cancellation than even its own previous headphones. First, the QC15 model really, truly does advance the art of noise cancellation — big time. The QC 2 headphones and my Panasonics cut the airplane roar by half. But the 15 reduced it by, say, 85 percent, leaving only a distant, whispery whoosh to remind you that you’re in an aluminum tube 39,000 feet up in the air. Taking them off after a while, as you’ll want to do because your ears get sweaty, is like walking into a rock concert when you’ve been outside the building. There is absolutely none of the hiss that plagues some rivals. Music sounds fantastic: crisp highs, solid bass, well-defined midrange. (Note to letter-writers: Yes, yes, I know: they’re not audiophile quality. For normal people, though, they sound great.) As with their predecessors, the cups on the QuietComfort 15 turn 90 degrees to pack flat into the included zippered (rather bulky) hard carrying case. That case also carries a detachable cord, so that you can listen to the armrest audio on the plane or your own music or video player, and a couple of adapters for the audio jacks on various kinds of planes.