There are some 1x12s that sound quite large and can keep up with some of the larger cabs out there. They'll have tuned ports for the speakers that help add depth i.e. CAA, Bogner, Suhr, Randall, Egnater, Mesa Thiele, Rivera, etc. These are especially good if you're wanting to do a W/D/W setup with a 4x12. I find the 1x12 cubes add some great focus for the wet effects in this scenario compared to, say, a 4x12. YMMV