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
I'm a novice although I purchased my first equipment in the 70s while overseas in the military. I now merely have a Yamaha N803 receiver and Vandersteen 1B speakers that are about 25 years old. I stream Spotify and have it set too the highest quality. I will probably upgrade but for now, I'm pleased that I kept the cost down, and most of my listening is background. I'm considering new speakers, probably from World Wide Stereo in Hatfield, Pa. near my home.  I heard and like their Focals.  Would I be wasting money with such a modest receiver or could I improve my sound considerably with new speakers.  Thanks for any advice.   Doug Hess, Newtown Square, Pa.
If you can, put speakers on the short wall, not the long wall. Start there. Find listening position with the best overall response. Tweak from there.
If the aforementioned suggestions do not yield the results needed, add a subwoofer. I recently ran into a similar issue. Found a little subwoofer at the thrift store and added it. Big improvement. Found a bigger better subwoofer on c.l. for a song. Daisy chained it together and it sounds much better. $60 and a couple sets of interconnects that were boxed up and problem resolved. Good luck!
Do you have another music source to try, aside from the TT?

It could be the TT/cartridge setup.

Also, what cartridge?

I asume that you meant Visaton and if so see if anything looks similar here in order to let us know what general type of speaker you have.

https://impactaudio.co.uk/collections/visaton-loudspeaker-kits-accessories#.VdoIMZdU4Q0

DeKay