Increasing bass on floor standing speakers


I have some floor standing speakers that were a Visation kit from 30? years ago. 
The treble and mids are amazing but the bass is a little weak. And suggestions on increasing the bass? 
Concrete floor 
Room 3.5 x 11 meters... Speakers on the long wall. 
Rotel ra-01 amp
Project rpm 4 (I think) 
Currently listing to Stevie wonder hotter than july.
Thanks for any suggestions 
speakerboyz

Showing 1 response by kingbarbuda

Two suggestions:
1. Mount your floorstanders on isoacoustics Gaia feet. 2. Add (REL) subwoofers.