I have used the Heresies in stacked combinations with other speakers, but have always thought they would stack nicely themselves. Right now I have them tweeter side down on top my LaScalas in my rock and rip it system. The Heresies add definition even though they are not as efficient. I personally don't like sub woofer, boomy, woofy, chuffy, woozy bass, so I don't think the defined bass they provide is a bad thing. If you want bigger bass get the belles or La Scalas or fortes. But you need a good strong power amp to control those big woofers,despite the popular assumption, that the efficiency doesn't require it. Stack em D'appollito style thats what I hope to do, let me know how it turns out. Before I do it myself. If your using it as a rock loud music system a small tube amp doesn't seem to do the trick. For acoustical music a single pair should work but they may not be the best choice, It sounds like you want big sound therefore I assume you want a loud system. The power amp that is working for me at the moment is an old Audio research d100b which I occasionally swap with other vintage period pieces like Sansui which lets you roll off the top end so they aren't shrill at volume. Let me know what your power is I am looking for suggestions.