Yes it will help with clarity. Issue is you need like HEAVY duty stuff as in wool would work or thick fabric that is fluffy. Downfall is it takes space.
Open celled foam that is like 3-6" thick and that will absorb all the back waves. Why thicker? How the frequency/ what frequency's are produced by the bass and they require greater area to eliminate back waves.
Hell, anything is better then nothing but if it is worth doing, worth over doing.