Well, that's technically not true, because I bought some Sonys several years ago, but I wasn't satisfied with them (in retrospect, probably a bad seal), and returned them soon thereafter. But this is the first decent pair I've bought since I've gotten into highish-end personal audio. I've never really had a good experience in with in-ears, due to comfort issues. But, I'm going to fly to California for Christmas, and I figured I should get a decent set of sound-isolating 'phones for the trip. I read a fair amount of reviews of the S4s, both positive and negative (I generally read the negative ones first, to get an idea of problem areas), and it sounded like the bass was pretty strong with these. Indeed, it's not always a good sign that the manufacturer advertises the earphones with enhanced bass right on the box. I brought them home and plugged them into both my E9 and stereo receiver, alternatively. Oh my fish. I think the bass, unequalized, is stronger than the Denon D1100s, and that's saying something. I immediately hit the Bass Reducer EQ on iTunes, and they got a lot better. The treble seemed a bit hot, too, and my receiver has bass and treble controls, so I turned the treble down a notch. Tasty. They're a bit thick, and maybe lacking some clarity, but otherwise very nice. It's kind of cool, coming from both open and closed circumaural headphones, to have nearly complete isolation, and being able to hear *everything*. Bass impact and amount is excellent now; still probably north of neutral, but I've never been one for neutrality. I found a good seal with the medium tips, the ones on the S4s out of the box, and comfort is excellent, as well. It's still kind of disturbing that bass would be a bit more than neutral even with Bass Reducer on, but a little EQing never hurt anyone, and I like them a lot now. Wouldn't mind a bit more clarity, so I'll probably let them burn in a while before passing final judgment, but so far, so good (provided I can EQ). Looking forward to the plane ride.