Speakers - coupling or decoupling?

Hi
I have a wooden floor that is on top of a concrete floor.

As far as I have read then spikes is good on at "sensitive" wooden floor and decoupling is good on a concreate floor.
But my floor is kind of a bit of both, so should I couple or decoupling?

I want to tighten up the bass if possible.

Today the speaker is sitting directly on the floor.
I intent to diy whatever it is I need - just at bit unsure of what it is I need 🙂
My own guess is decoupling, but please let me know what to do 🙂