If you already have a pair of Denon D1001, then that's a pretty decent pair of closed headphones. If you want something that's very laid back and not tiring, definitely consider the Sennheiser HD598s. These are probably some of the most relaxing and enjoyable headphones I've used to date. Only drawback of them is that they tend to be a bit bass light, which might not make them the most exciting things for action movies or hiphop. However, they are very smooth sounding, detailed and huge soundstage. I think they would complement your D1001's very well as it kinda offers the opposite.