Wow - did I "under think" this aspect of my home theater, or are others "over thinking" this??
Truly I ask with genuine interest, and I've been know to go OCD on some items....
What I did, fwiw.
(my basement HT is on a slab floor, premium carpet and the best pad I could afford under the carpet, quite thick/plush.)
a) Floorstanding speakers.
My Paradigm Monitor 9's came with outboard feet with spike's, I use them to angle the speaker slightly above the first row so the people in the second row don't get the mid/high blocked.
The rear spikes are almost all the way twisted in, there is a lock nut, the front spikes are not quite all twisted out. Both them "punch" into the carpet.
I have blue painters tape on the carpet to align the speakers in same place when I move them for cleaning/etc, so no need to re-run audyssey.
b) Center channel
My center channel is below the HT screen, I made custom wood blocks to angle the speaker above the first row so the people in the second row don't get the mid/high blocked.
I also used soft sponge like material, its black and I think used to line cabinets for glasses/etc, you can see it between the wedge and the speaker, it is also between the wedge and the shelf base.
It keeps the speaker in place nicely.
and I was hoping to isolate the speaker from the shelf somewhat with it....but not obsessed with that aspect either.
The center channel front is slightly ahead of the shelf edge, so no edge sound diffraction issues.
The shelf is attached to the wall, when I built the HT I put treated 2 x 4 's between the engineered concrete foundation studs, knowing a center speaker would be there. It is very solid.
You can see my drywall guy leaning on them here
c) My 11.1 wide speakers
I made these in-wall recess area to hold them, the bottom shelf is lined with same material used for my center channel, I had it leftover from the project.
Also, use bumpers in the front to tilt these slightly above the first row so the people in the second row don't get the mid/high blocked.
(the recess is lined with 2" OC703 also)
So, I've used both spikes and "soft material" for what I think is a practical usage of them, am I missing something here???