Tried the MK2 with my new pair of Beyerdynamic T1.2 (600Ohm). They sound incredible and I have to say that it is by far the best setup I had until now. So my worries related to Beyers is gone.
But keep in mind the following:
- T1.2 has a more bass than original T1 but still they haven't lost the detail
- T1.2 has less treble and does not sound harsh at all
- Comfort is incredible, compared to T5p (my other Beyerdynamic I own), foam pads are incredible
- T5p cannot touch the T1, they are in different leagues even if they have the same price
- T1.2 are not "unforgiveable" as some say, I tried different recordings and I have to say that some "poor" ones sounded better than on my HD600 which are "veiled" and bassier and should be more forgiving
- Drivers used were Mullard M8161 - the most neutral ones I own
- I prefer a clean and detail sound, and I am not enjoying too much bass, but precision
I tried the T1.2 directly in NFB11 (neutral) and it does not sound bad, but worse than on tubes, more "metalic" and cold.
Plugged directly on iDAC2 sound better than on NFB11 (warmer somehow) but not as good as on MK2. So we have a winner, and it seems that again the price is not the first thing to consider when amplifying high end models like this one.
So in conclusion, 600Ohm headphones work fine with MK2, no problem at all. And T1.2 is an incredible pair, far away from T5p and most probabily an improvement to original T1 in terms of bass and overall musicality.
I hope my comment is useful for someone.