what do you put under your sub?

Jaff2290

You won't need spikes....I doubt the concrete will interact much with your sub except to reflect energy...carpet and under carpet will provide damping to reduce any chance of rattle .....so why mess with it.

If it sounds muddy you may have room mode issues.....nothing to do with what your sub sits on but partly related to where it sits and the room shape itself.

In my previous post, I made the assumption that the sub cabinet does not resonate in the frequency range you are using it for....if you have a cabinet that resonates (side walls waffle) then you have serious problems...coupling to something massive, like the concrete floor may help to dampen this but cabinet resonance means you will have distortion, especially on transients....normally a sub will be solid and very heavily braced internally to prevent this happening (i.e. no need to couple it to something solid in order to stop it resonating)