Why do you recommend the NDH 20 for mixing purposes?
Monitor headphones used by musicians during recording session are normally closed to minimize crosstalk to the microphones. Open headphones are often used for mixing and mastering. The NDH 20 is equipped with a very linear frequency response, although it is a closed headphone and suppresses external noise very well. This makes it possible to edit and mix finished recordings even in noisy environments. A detailed review can be downloaded here: NDH 20 review.