For as much as we get asked about amps and EQ, we should really get EQ and amp info for the SZ1K's and SZ2K's stickied. lol
The Fiio A3, Fiio E12, or Cayin C5 can amp these cans to perditions flames if you want to take them that far.
I personally like external EQ's rather then software EQ. If your your not connected to an external DAC and are running directly off your headphone jack, you might find software EQ to be less then desired. This is because the pre-amp in your phone, computer, or many other music sources lack line level amplification. My personal setup however is home theater, so it just made even more logical sense to get an external EQ box and set it up so all sources running through my tv get equalized. Hardware based EQ's have their own amplification, and they have a transformer large enough to provide the output.
However, if in your case you are going portable with your phone, I would highly recommend that you get the Fiio E18 DAC/AMP combo, then you can do software based EQ on your phone and it should work out perfectly. Since I am not the type of person who likes to talk out their *** about the stuff I speak, I will provide a picture of my latest EQ settings so that you know how you can get the most out of them. Oh and don't forget these have burn in, so the longer you use them, the better they sound.