Higher impedence is better

Want to get the best earphones? Look for a higher impedance, measured in ohms.

Here’s a comment from someone on Digg. I don’t know if it’s true, though, so read with a grain of salt and do your own research.

Most of these headphones on this site have impedance ratings of under 60 ohms, this is NOT good with the iPod as it will attenuate the bass and cause distortion (do a search around the internet for ohms and iPod to see what I mean). The iPod performs best with headphones that are a min. of 60 ohms, the higher the better.