At present, we can only choose momentum. K70 1 and hd650 are well-known high impedance headphones. Without a desktop system, it is impossible to produce good sound. Momentum is specially designed for idevice equipment, with wire control, which can also make a good sound under general reasoning conditions. Good players also have good results. Besides, amperior may also be suitable for you. It is a low impedance version of hd25, and the effect is good. Remember to take my advice. In addition, the portable front end of k70 1 and hd650 can be pushed up completely, but it must be installed in the ear room.