WITH DIGITAL AUDIO players becoming as ubiquitous as cell phones, headphone sales have grown 66 percent in the past four years. Along with improved sound quality, the most important developments have been wireless Bluetooth compatibility and noise-canceling technology. The former is a boon to active types tired of battling wires on their morning runs, while the latter, which cancels out ambient sound by smothering it with inverse waves, can save your ears. "It's great technology," says Andy Vermiglio, senior research associate at the House Ear Institute, a Los Angeles–based hearing research center. "You don't have to compete with the outside sounds, so you don't have to turn up your music. As a result, you'll have less risk of hearing loss down the road." So if you're serious about your music, go for one of these state-of-the-art systems.

1.) Motorola HT820 »
After more than two years of R&D, Motorola's first cell-compatible Bluetooth headphones hit the pavement earlier this year with sleek looks, sound like seventh-row center, and earpiece controls for volume, track choice, and call waiting. $120; www.hellomoto.com

2.) Jabra BT620s »
Talk about a multitasker. This Bluetooth headset simultaneously syncs with your cell phone and music player, employs push-button earpiece controls, and packs a lithium-ion battery that delivers 16 hours of talkin' and rockin'. $129; www.jabra.com

3.) Bose QuietComfort 2 »
Bose, the inventor of noise-canceling headphones, remains the master at designing muffs that drown out traffic and crying babies. In addition to providing a solid fit, the QuietComfort 2 generates orchestra-like volume that makes your head feel like the inside of a concert hall. $299; www.bose.com

4.) Altec Lansing iM716 »
Unwilling to commit to the bagel-size headgear required for true noise-canceling phones? Altec Lansing fills the gap between the convenience of earbuds and the sound quality of full-size sets by wrapping high-definition speakers inside baffled plugs. The result: Nothing but your music reaches your inner ear. $200; www.alteclansing.com