Not to sound like an ass, but it's kinda impossible to get MOREBASS without an amp. The XB1000 are basshead cans, good bass w/o being really muddy (like the xb500) however they are mostly sub bass.
Iems will likely have the bass you want because they don't NEED an amp, and I honestly haven't heard a pair of cans I can listen to w/o one.
Yeah I understand, the thing is I've stopped using a portable amp while ago and don't invest in iem's no more, I was just wondering if there is a can that has more sub/mid bass than the XB1000 in it's stock default form - no amp or whatever. Money is not an object to me.