I have decided to sell my MDR-CD3000's today, after I bought a pair of Beyerdynamic DT531 headphones for someone else. I have owned these headphones before, but never with an amp of the caliber of the Perreaux. Surprisingly, these DT531's are sounding better than my Sony's with my kit (TerraTec EWX 2496 sound card, Perreaux SXH1 headphone amp), admittedly a smaller soundstage, not quite as clean and clear or not quite as dynamic, but the 531 comes usefully close in all of those areas, and to boot, seems to have significantly more bass punch than the Sony's and just basically has a more enjoyable sound. I can come to only 2 theories why this is. Firstly, is that the Sony's are simply too good for my system (quite possible I admit). The second is that these DT531's are simply ridiculously good for the money. I would say its somewhere half way here. I would say that the Sony's probably are overkill for my system, but also that the DT531s are REALLY good cans. I always had a soft spot for them mind, and never heard them with a really good amp before like the Pereaux - until now. I am pretty shocked to say the least, but I hope this thread should serve as a potential warning to those partnering very expensive (i.e. £150+ headphones) with midfi componenets - as this proves, it is possible to get a very good result without spending a fortune.