I currently have a Denon D2000 setup connected to a Nuforce Icon Mobile DAC/AMP (connected to my Macbook Pro via USB), which has provided a measurable improvement in performance. While I plan on getting wood cups and the Marklmod in the near future, I was wondering if forum members could recommend a next step DAC/AMP (doesn't need to be portable). And are there noticeable benefits in moving to a "better" DAC/AMP?
For instance, would going with a more powerful Nuforce (the Udac 2 for instance) improve the SQ with the D2000s? Or should I save and consider something like the Graham Slee Voyager, etc?