As a FH5 and IMR R1 & Zenith owner, I can say that with a DD that large it has the potential for alot of bass. The filters will probably make the difference. One graph with no labels as to which filter was used won't explain much. More than likely, it was probably the neutral filter to give a baseline reading of sound. We won't really know until more graphs are available with the specific filters labeled and they are reviewed. People say that the FA7 is darker sounding than the FH5 but with less bass so who knows. To me, it would seem that Fiio is giving us a choice of preferred sound. Again, I mentioned the IMRs because of what filters can do to sound. Iems can be treble cannons or mini subwoofers with the proper filters. Hopefully, Fiio has implemented this ability properly on the FH7s. Only time will tell...