Are you using Rockbox on your Clip+? I'm using the same combination with an EQ on Rockbox and it literally gives me the chills from the bass.
I recommend a Rockbox Clip+ is seriously a must if you want the heaviest bass possible.
Have you auditioned the HFI-580? To tell you the truth, I'm happier with my 580's bass when listening to EDM using the Rockbox Clip+ and E11 combination because it's just more fun!
The bass is punchier and you feel more of the bass with the 580. It's excellent if you want a quality, clean alternative to the Beats (fun bass you can feel).
The Pro 900 is more of an audiophile bass.




























