Both AKG k271 and k240 are fairly light on bass, the k240 less so than the k271, so keep that in mind.
$100 dollars for a pair of k271 is a good deal, but they are a bit difficult to drive, thus a good soundcard/headphone amp will get almost 2x the bass out of them than compared to an ipod. The bass will still be a bit light, and thus should get some bass boost, especially for drum and bass.
All of the headphones you listed are 'high' impedance headphones to some level, thus all of them will benefit from a proper high impedance headphone amp.
One pair that you've missed are the AKG k181dj headphones. They are sealed, have better bass than the k240/k271, are easier to drive, and obscenely loud. They should do quite well for the DnB
$100 dollars for a pair of k271 is a good deal, but they are a bit difficult to drive, thus a good soundcard/headphone amp will get almost 2x the bass out of them than compared to an ipod. The bass will still be a bit light, and thus should get some bass boost, especially for drum and bass.
All of the headphones you listed are 'high' impedance headphones to some level, thus all of them will benefit from a proper high impedance headphone amp.
One pair that you've missed are the AKG k181dj headphones. They are sealed, have better bass than the k240/k271, are easier to drive, and obscenely loud. They should do quite well for the DnB
















