Should I decouple my subs too?

Put a 2' square paving slab on the floor under the sub, and sit the sub on 4 Nobsound springs.

@noromance  

interesting idea I’ll look into that as well 

An inner tube works really well to.. TO see if that's what you want.. No kidding. Air it up give it a listen. If it's good (It will be), gussy it up or get the Nobound or what ever you like.. The inner tube does work good though.. and you can adjust the dampening. George reminded me of that... I used the inner tube thing on 500 lb bass bins.. Stopped the waves in the neighbors pool, too...

This may sound kind of weird. BUT it doesn't have to be completely de coupled.. I tip one edge to get an angle with springs sometimes and set the other on the amount of dampening I want.. Could be another set of springs, a block of wood or just carpet rolled up. You can control the amount you want to feel through your BUTT.. Some times you need. 

Ex: A recorded live concert. It's not suppose to be perfect.. Suppose to be a little Boom Boom in the Room Room.. LOL

Regards

 I just got off the phone with the REL guy and he said NOT to put footers on the subs as they perform better coupled to the floor. 

If you would like I have a long list of manufacturers I can put you in touch with, every single one of whom will tell you their products are so perfect nothing you can possibly do will ever make them any better, might void your warranty, and quite possibly be fatal. 

The last thing I would ever do is ask a manufacturer how to make his product even better. Worst thing you could ever do.

@oldhvymec. 
Very cost effective idea. I like it !