Lots of bass at walls, lack of bass in center of room/listening position


I guess this is relatively common in listening system. Is there any way to smooth this out so I get more bass energy at my listening position? This happens with our without my 2x 18 inch subs. Room is 12 x 16 x 8 ft, speakers 4.5 ft apart on long axis and I am sitting 4.5 feet away. I tried moving back and forward but the entire middle center of the room except near the walls has decreased bass.
Is this a boundary effect or could it be due to bass cancellation effects?
smodtactical

Showing 2 responses by m-db

Your room is absolutly unique regarding the positioning and integration of a subwoofer/s. Other people's dimensions and locations, even if they're identical or similar, will require a great deal of trial and mostly error.

If you locate a sub at the listening position by using long enough interconnects (Monoprice or Bluejeans Cable) and an extension power cord while playing low frequency tone/s will allow you to walk (or crawl) around your room and map out YOUR rooms modes and nulls. This test tone download should be useful https://realtraps.com/test-cd.htm

This method is simple and need only be done one time. Once you've mapped YOUR room you can experiment by placing your sub/s at or very near the mode (louder bass) areas.

I found multiple subwoofers evened out my rooms modes. Controlling the subwoofers frequency response is a product of equalization and room treatment (Eric's blog). No amount of subwoofers can control frequency. While using four large subs I found equalization absolutly made such a desirable improvement I found two small subs to be sufficient. Then again, along with personal taste every room is unique. 
This is well worth the effort good luck with it.