When I talked to a friend last night, I mentioned DT1350 by the way. It happened that he was paying attention to this recently, and he learned from a computer store in the computer city that he had to listen to it, so he went to it today. 
Special note: The new machine is very tight, and it is especially uncomfortable to wear it on the ear for a while. You have to take it off and take a rest. But I believe it will not be so tight when it is opened. 
Briefly talk about the sense of hearing:
I am surprised that this small body can come out such a low frequency, and the focus is on the low frequency, the high frequency and the intermediate frequency are not overwhelmed. Although the contrast of the Philips X2, the sound field and the resolution are slightly less; compared to the level and stereoscopic sense of the X2 Although DT1350 can also be heard, but the whole is more compact; but this kind of volume can come out with this effect, I really feel unexpected, especially the low frequency, very deep. I think it is better than X2, even can say, contrast X2, its high frequency is simply enjoyment. X2 has a kind of "muffle" feeling similar to Senhai (especially HD650). The most obvious point is that the music in the music and the rhythm of the sound are clearly distinguishable. The X2 can only hear a "silk" sound (not to rule out the problem of my EQ setting, I cut the high frequency completely, because the tooth sound is particularly harsh).
Not long ago, I entered the SONY PCM-D100 and Philips X2. I feel very satisfied. I don’t think X2 is too big (not as big as possible, you know). It’s a torture to go to work every day; it happens to be online. To Beyerdynamic DT-1350 several posts introduced this headset; in fact, it was poisoned when I saw it, but after all, the earphones, the beauty can not be eaten, the key has to look at the sound quality, after all, this is fundamental. The box is really stingy; it can be seen from the comparison with the iPhone 6 in the picture, it is really small. Open the box, inside is a pure black earphone bag; open the package, you will see the body. The earphone itself is black, engraved with the byerdynamic logo; wearing the skeleton with metal; the leather earmuffs are very soft. It must be said that the rotation of each joint is very smooth and very fine. The only thing that is lacking is the leather cushion on the head beam. Perfunctory, and the work is very poor, like looking for a piece of scrap to sew up. There are several versions of this headset, the material and sound quality are different: 32 ohm version, 80 ohm version, CC version (that is, the phone line version).
And SONY PCM-D100 fit.