The bass hump on the Superlux is MASSIVE compared to the AD700, which would alter our perception of it's sound signature quite heavily. The upper mid and lower treble regions have between a 5db to 10db difference, which is also night and day and give a completely different upper range presentation.
I highly doubt they sound anything alike. The Superlux looks v-shaped, while the AD700 is mid and treble oriented.
I haven't heard the Superlux. Just going off those graphs, I have a good idea as to what to expect from it especially when comparing it to something I do have good experience with.
In fact, the superlux as almost an identical graph as the Portapro/sportapro all the way up to the upper mid hump. Both of those are pretty bassy. The complete opposite of the AD700s. You can't analyze sounds as well with headphones with that much bass emphasis.