Something else I should have mentioned, amping the 940s adds more weight to the bass, so that might be enough if you find the bass a touch too light. The treble and mids still maintain their weights relative to each other, though.
Regarding "neutral sound," I don't believe that it exists. In headphones, bass always rolls off somewhere, there's always some curving of frequencies that progresses from bass to treble, and the treble frequencies always jump around a bit. I have no idea what the technical reasons are, but you can see it in every frequency response graph for headphones. So the best you can get is something that sounds neutral to you.
And that's after someone's recorded the music with non-neutral equipment, EQ'd and processed it, and your transport/DAC/amp has done things to the signal before getting to your headphone, then to your non-neutral ear and taste. :)