Has anyone thought of actualy fastening speakers to the floor, the whole idea of feet, spikes and etc is to keep the speakers casing from moving at all, only the cones'n'domes should produce any sound, if you are fortunate enough to have a concrete floor, some suitable masonry expertise should render the speakers absolutely immobile. Wooden or chipboard floors are a different problem, each situation would require its own particular 'tweak'
Martin
Martin