I think I need more bass traps, where to place them??


Hi guys, I already have bass traps in all four corners of my room but I still have some pretty bad room modes resulting in big peaks at 60/120hz and dips at 80/160hz.

I spent hours and days messing around with speaker placement and my current setup is the best I can do in terms of matching my target room response curve aside from these modes.

So my question is...I assume I need more bass traps?  If so, what is next logical position for them?  Sidewalls?  Front wall between the speakers or directly behind speakers?  Back wall?  If the answer is yes to all positions, then where should I start?  Due to financial restrictions I would like to treat one area at a time.

Thank you!
128x128tboooe
Thank you for the post guys and sorry for not being more clear. As @onhwy61 mentioned my room is almost a cube at 10’ l x 9’ w x 9’ h. Note that the back wall behind me is 36" tall, above which the space opens up to my family room and kitchen. Because the room is almost a cube I cannot tell from which dimension the axial mode is coming from.

I know that my Right speakers has peaks at 60/120/180 and since I sit with my back right against the short back wall, I have to believe this is being caused by the length axial mode which has max volume of all the modes at the extremes. What I dont understand is if I want to try to address the length axial mode should the bass trap go directly behind the speaker or on the back wall behind the seating position?  Even though the back wall is only 36" tall, it is only about 2" lower than my ear height.  

@geoffkait I am not sure I understand what you are suggesting. I measured my room response only from my listening position so isnt this where the wave is?

@erik_squires and @bdp24 I do use EQ with REW. I found that peaks are dealt with effectively with EQ but dips do not improve much.
Tbooe wrote,

@geoffkait I am not sure I understand what you are suggesting. I measured my room response only from my listening position so isnt this where the wave is?

The wave at your listening position is determined to a large extent by the other waves in the room, waves like reflected waves, standing waves in room corners, standing waves anywhere in the 3D space. Waves interact. It's quite possible to be sitting right in the middle of a standing wave.
I had great success with room equalization and did it all in the analog realm without spending much money.  I had a major issue with boomy bass in a small room last year.  I got an XTZ room analyzer Pro and it identified a big room mode at 38hz, suggesting a -22db correction. I attenuated it down about 15db with a McIntosh MQ 107 equalizer and the boomy bass issue was completely gone. One of the most immediate and dramatic changes to my system ever.  I think the digital room EQ devices work well too but the analog equalizer I got is from the 1980s and was very inexpensive.  Would be worth a try. 
Contact GIK acoustics for help, and you may need to place your speakers like they were 2 subs.  What I mean is, you may need to place 1 speaker, and then look for the best location for the second. Use a mic to find the locations that have the worst nulls and try to put the second speaker there. :)

Best,


Erik
tboooe, the reason eq doesn't help with the dips is because they are "nulls", the rooms dimensions creating frequency cancellations that no amount of eq can correct for---an infinitely deep hole at null frequencies. The only way to deal with nulls is to move the speakers around, the find a location where the nulls are shallowest.