My TAD CR1 MKII stand-mounts (46Kg) come with TAD's matching stands (18Kg) which are of a dense wood construction!
Several options exist for the floor interface, including steel cones that screw into the underneath of the stands to form a stable tripod. You can, of course, use nothing, as the speakers and stands are quite stable on a carpeted floor, or, as I elected to do, initially, screw in a trio of Stillpoints Ultra 5 footers, which does raise the base of the stand (and tweeter) from the floor.
I lived with this arrangement for five years and was always content with the "fruity" strong bass performance, which has no right to emanate from a stand-mount speaker system.
My house is of modern construction, having been built in 2013 and the regulations that were current at the time, specified a membrane to be used to seal the concrete floor and I believe some sort of insulation was applied, before topping with MDF, with underlay and carpet on top.
So, the floor is not carpet/underlay over solid concrete floor, although there is no void to contend with!
I recently swapped out the trio of Stillpoints Ultra 5 footers, with a pair of size 4 Townshend Audio Seismic Podiums with blue springs at the four corners to accommodate the combined mass of the speakers and stands!
This arrangement lowers the base of the speaker stands (in comparison with the Stillpoints) which now hover less than an inch from the floor.
I was initially shocked at how much the presentation of the music changed, with detail, clarity, imagery and soundstage all enhanced, together with a tighter, more extended bass response.
There was obviously a lot of bass energy that was feeding into the floor, when Stillpoints footers were employed and this energy was influencing the sound of the system.
I am convinced that the Townshend Podiums are an improvement over a conventional speaker floor interface and although expensive, are an essential addition to any floor-standing or stand-mount speaker system used in a room, without a solid concrete floor.
By isolating the energy that the speaker feeds into the floor, vibration is also drastically reduced in reaching source components and floor standing amplifiers!