I had a very interesting discussion a few years back with the proprietor of now-defunct Virtual Dynamics cables on this specific target. In both of his demo rooms, he was using Parsifal Ovations as speakers. In one room, he had also used an amp that he developed. I had just bought mine a few months before the show, and I told him that I felt I needed to lift up the speakers a few inches to get the tweeters on the same height as my ears, and I felt I needed to slide down when sitting in my chair to get better sound. He then show me a pair of these custom-built outriggers he uses with his personal pair of Parsifal Encores back home. He had brought them to the show and used them on the ovations.
He also told me about the ones Symposium put out specifically for the Parsifals. He offered to get me a pair of the outriggers, but I thought they were a bit expensive. Mine sits on top of a 2-inch thick hardwood chopping board from IKEA. The board is on hardwood floor with a thin sheet of vibration absorption sheet in between. The bass unit sits on top of a set of Cerabases. The whole thing elevates the speaker about 4-inches, and my new chair is lower than the old one.
FrankC