Bass trap is special resonance construction which is able to absorb low frequency resonance of your room. It is very common problem for anybody who decide to build good critical listening room or Studio Room.

There are several solutions which can be optimal designed for your purpose.

The construction might be heavy but able to be moved in corners or on the wall.

On the other hand we used to integrate such resonance construction in wall or ceilings, so as result you can have very balanced room in low frequency spectrum which gives fat to the low-end sound of your speakers