the SP II model SUCKS for anything but DJing maybe.
they have no bass even after 20 hours of high SPL dubstep break in and gave me headaches trying to listen to them for long stretches as they're so bright in the upper midrange & lower treble. i was furious when i bought them as they didn't sound like $200 phones should and i didn't even think they were worth $95. i'd rate them as $30 headphones at best for everyday use.
they can play insanely loud without distorting and have tons of speed and detail, but a rolled off bass and amped up treble that makes them sound like tiny bookshelf speakers. even my little NHT superzeros had more bass. i stopped using them the second i brought home a pair of $50 AKG K44s. those have acceptable bass, though still a little polite and a much smoother treble response with excellent low level resolution and speed if a bit of spotlighting on siblants that tells you when a track was recorded with too much treble.
they totally ruined the sound of binaural recordings which sound much more natural on even $30 semi-open JVCs. they impart a closed in almost plasticky sound that destroys the imaging & ambience of a good binaural recording.
for the price difference, i imagine the studio version has better drivers and a flatter frequency response and that the SP IIs are designed to cut through the noise of a DJ rig at full volume more than be fun reference instruments. i didn't care for the grado style swivel cups one bit either.
Edited by zeroemission - 2/6/12 at 10:52am