The TLDR is just what the title says...

The long version is, I have a pair of M60 Ti towers and I love them. They sound(ed) fantastic, completely satisfied by their performance, no reason for me to pursue anything better. Then I moved house. Now they sound markedly different... and not very good. They're still strong and clear, it's just that they've lost the sharpness and "sparkle" on the upper frequencies, and the depth isn't there at all. One of my friends described it like "it sounds like you threw a wet towel over them." He also owns a pair of M60s, and his, at his house, sound exactly like mine did at my old house.

All of my equipment is the same down to the speaker wires and interconnects. The listening distance is also the same. The room is smaller than before, but it's still larger than the room my friend has his M60s in. I ran the calibration sequence in my AVR but that did little to help. I'm thinking the difference in sound has to be because of the construction of the house. The old house was a concrete foundation with tile flooring and concrete exterior walls. The new house has a concrete floor downstairs and wood upstairs. The room where the speakers are has a wood subfloor with "floating" vinyl plank flooring, similar to laminate, and the exterior walls are also wood frame.

I'm guessing the wood subfloor has to be the problem. I got my M60s second hand and they came without the original feet so I did a bunch of research on speaker feet and read all about acoustic isolation and different kinds of things that can change the sound of a speaker, including odd things like putting sand bags on top of speakers, or placing speakers in a pot of sand to "decouple" them. Some people described different methods of isolation as having a profoundly positive effect on the upper frequency range and even the mid range. Well it seems I'm having the opposite experience.

My question is, has anyone else had this problem, or had any experience with acoustic isolation/decoupling with Axiom speakers? I don't know where to start other than pouring some 80lb concrete "tiles" to set the speakers on, hoping to mimic having them sitting on a concrete floor. That would raise the speakers up some, which may or may not be an issue.

Any advice or input would be very welcome. I very much want the amazing Axiom sound quality back.