these headphone be wonderful . they be the best pair of headphone I have ever own . I consider myself a audiophile . I have no electronic background but have purchase many high-end piece of audio equipment over the past 30 year . I currently own several headphone include the ah-d2000 -lrb- I purchase these for my daughter -rrb- and the Ultimate Ears triple . fi10 earbud to use when I travel . I be sure I would love the ah-d7000 but I feel the $ 600 difference be probably not justifiable . I be able to purchase these for $ 399 . there be a small , but noticeable , sound quality difference between the 2000 and 5000 headphone that I feel the less than $ 200 difference between they be worth it . Bass be deeper without distortion . Treble note be crisper . midrange be fuller . although I can listen to classical music , my preference be classic rock . Pink Floyd dark side of the Moon and The Wall sound fantastic . Led Zeppelin be amazing . for those that have comment that these headphone need a external amp to drive they , I disagree . although the majority of the time I listen to they use my Pioneer Elite receiver and they sound great , I plug they into my ipod and they sound very good . the quality of the music be not as full , rich , and `` powerful '' sound but more than I expect , especially give the review I read . I do not know if I would opt for the 5000 over the 2000 if the price differential be over $ 300 -lrb- I have see they from $ 399 to $ 699 -rrb- ; but , I feel it be a bargain at the $ 140 difference when I buy they .