I used brass cones 6mm thread with “t” nuts on my former Odyssey Kismet Floorstanding reference speakers and used them with the protection cups sitting on a slab of polished black granite. I had no concerns about the sound. I replaced the speakers with GE Triton Reference speakers and use the GAIA II with them and their carpet spikes. I can’t compare the two but the GAIA made a noticeable impression which I love very much.