The L1 is peculiar, described by Philips as semi-open, and while it does not have the best of either world in soundstage or isolation, if offers something that makes it a bargain at the price in my opinion. The L1 played flat has big bass and very good mids and highs, but with bass reduction becomes one of the best hi-fi headphones under $900 USD or so. The very strong bass even with bass reduction may mask less-than-ideal mids or highs, but all I listened for was the overall sound flat and bass-reduced. And that sound is exceptional (albeit somewhat dark) for $300, and still a good value at twice the price I think. It's full sized, yet totally portable and wearable around the neck all day without any bother.