emcdade, that is my concern. My carpet and pad is about an inch thick uncompressed. If the carpet spikes are 15mm, I'm not sure the carpet and pad will compress enough to made solid contact with the subfloor. It looks like the spikes aren't long enough or tapered enough to work effectively in my application.
Isoacoustics Gaia Speaker Footers
Replacing the spikes in my Soundocity outriggers (Soundocity made me a set of outriggers with threaded holes) with the Isoacoustics Gaia 2 footers has improved the sound of my Merlin VSM speakers. They now sound more open and articulate than with any combination of Z-feet or other spikes, with or without outriggers, on the floor or on a platform, that I've tried. Like the Townshend products the Gaia footers completely decouple the speakers from the floor, allowing them to float. See:
http://www.audiostream.com/content/isoacoustics-gaia-isolation-pucks#IVXH8EtVAjQdwbuj.97
http://www.isoacoustics.com/products/gaia-series/gaia-i/
http://www.audiostream.com/content/isoacoustics-gaia-isolation-pucks#IVXH8EtVAjQdwbuj.97
http://www.isoacoustics.com/products/gaia-series/gaia-i/