so, I got some updates ....
I've purchased both, Auralex SubDude and AmpDude. Even though I think AmpDude was designed for an Amp and not a sub... still gave it a try.
To keep it pure, I decided to test out the 3 options (no riser vs subdude vs ampdude) using my SACD player music running in EXT-IN setting .. meaning pure pure. So, no audyssey correction or anything.
This was a good workout. About 7 times had to lift my 50lb or so Sub. Going back and forward with the same 2 songs.
Results ... It works !!!
I do lots if A/B testing with equipment. It's not always 100% scientific as I only use my ear to judge, but this one was one of the easiest A/B testing I've done.
Keep in mind, my sub was on the wood floor. So, going from wooden floor to a riser helped.
When I placed it on the Subdude ... sound became a bit easier on the ear. Floor vibration calmed down a bit but was still there. To me, it was somewhat an improvement. However, once I placed the sub on the AmpDude ... now it became very pleasant to my ear. Eliminated floor vibration probably by 50%. Good enough for me. It seems like it eliminated the unpleasant hum, or whatever you may call it. Bottom line ... bass was now a part of music instead of vibration.
Keep in mind, my Sub is pretty decent. Rythmik F12 (almost a thousand bucks). Some people said that risers work only for cheap subs. I disagree now.
Anyway ... I have yet to test the sound now with Audyssey on some hard hitting movies but I am assuming that now I'd need to rerun the room correction software before I proceed.
Again, going by just pure source from SACD player ... bass became much much nicer to feel.
I now wonder what those ATS 2 in panels will do for me once I start covering my bare walls.