[sonorlite]

I have a 13x11x8 room with two GIK Soffit traps in the rear corners with Tri-Traps stacked on top and 4 stacked Tri Traps in the front corners. I have been having an issue with tonal imbalance where the upper bass/lower midrange (200hz-700hz)  is very thin compared with the frequencies above this range.

Looking at the GIK data for these traps, they produce a lot of absorption in the range from 100hz to 500hz and considerable less above (almost double in Sabins). I know it's an easy fix to try but has anyone experienced a similar issue with bass traps overabsorbing the lower midrange?

[kingdeezie]

Do you have side wall reflection treatment? Perhaps the lower midrange is spot on, but your highs are reflecting and echoing.

Also, did you try moving the speakers? As your response gets more even with the treatments, location within the room makes more of a difference.

[sonorlite]

I do have side wall and ceiling absorption panels and the bass traps go all the way up to the room corners. I tried moving the speakers both closer anf further to the wall behind them and also closer to the side walls with no effect on the deficient frequency range.There was an increase in low bass closer to the wall behind the speakers as expected.

[richidoo]

Make sure your speakers are outputting flat frequency response. Midrange imbalance isn't usually caused by room modes. Because modes created by midrange wavelengths are more closely spaced, if there were any bad peaks or nulls you would hear them when you walked around.

Speakers' baffle step correction exist/working?
Check the amplifier connections.
All reflex ports not obstructed?
Bass tone control turned down?
Old output tubes?

[CSI]

I have used GIK products for years and they have done a great job in various configurations in making my lousy (10'x10') room listenable. However, they are either added, removed or moved around whenever I change gear - particularly speakers of course. The one constant has been the rear corner bass traps (5" thick panels). They always removed an annoying midbass hump. Until now. I recently bought a pair of Decware DM945's and although they sound fine with the traps in place I read on their site that they often work well in rooms with little or no treatment. I was skeptical but sure enough, removing the bass traps increased the sound stage, brightened up the top end and improved the bass without boominess. The bottom line is - always experiment.

[Glenn Kuras]

You may want to drop Bryan an email with pictures and info on you room to look over. It might be a matter of just moving things around a bit or adding a few more things.  You can contact him at the following link.
http://www.gikacoustics.com/contact/

[SoCalWJS]

Have you had an opportunity to take some measurements? That may confirm your perception of thin at those frequencies or point out a bump elsewhere. It sounds like you have lots of absorption so I would definitely try to get some measurements if possible.