Shure E3c Sound Isolating Headphones, $179.00
Unlike cheaper headphones, Shure's model fits into the ear canal, blocking out ambient noise almost completely. They also provide crisp, studio-quality sound that gets better as it moves toward the high end of the spectrum, making the model slightly more suited to jazz, classical, rock, and vocal music than hip-hop or soul. Plus, the Shures boast an iPod-friendly design (white earpieces, gray cord), and a "personal-fit kit" (which comes with a variety of foam and plastic sleeves). What more could you ask for? Well, a thinner, more flexible cord would have been nice—I had to tie mine with a rubber band to keep it from snagging on subway turnstiles and Nautilus machines. So would a lower price: At $179.00, the Shures cost four-and-a-half times as much as Apple's upscale model, and two–and-a-half times as much as the Grados.

Grades:
Comfort: 4 points
Design: 4 points
Sound: 5 points
Privacy: 4 points
Overall: 17 points

Etymotic Research ER-4P, $330
"Etymotic" means "true to the ear," and these handmade headphones (also designed to be inserted deep into your ear canal) live up to their name, making recordings I've listened to hundreds of times sound utterly new—I could hear the scrape of Joey Santiago's metal guitar picks and the sound of John Coltrane's saxophone valves opening and closing. Because they fit so far into your ears, the ER-4Ps block out ambient noise, and unlike the Shure E3c headphones, they come with an easy-to-handle five-foot cord. But at $330, they're brutally expensive, costing almost as much as a 40 GB iPod. All the same, test them out, and you might be tempted to max out your credit card. They're the only perfect model I tried.

Grades:
Comfort: 5 points
Design: 5 points
Sound: 5 points
Privacy: 5 points
Overall: 20 points