Shouldn't This Sound Boomy?

When looking at response, 5dB/division please.

Bass looks okay. I would tame that one peak.

The dropout at 2K is a far bigger problem. It’s 10db. That is very audible. I would prefer more slope at high frequencies.

You said you had panels. You may have too many of them may work over a narrow frequency band. Fully carpeted?

@larry5729 the system is a Hegel H390 integrated amp and an Audiolabs 6000 CDT Transport using the Hegel's internal DAC. The speakers are Tyler Acoustics Highland H3.5s rear ported three way speakers. The room is treated with 4" diffuser panels on wall behind the listening position and a 2' x 4' x 4" bass absorber behind each speaker and a 2' x 4' x 4" diffuser panel on each side of the speakers. I have a stack of rockwool panels centered behind the listening position at the floor.

@theaudioamp the room has an area rug covering the entire floor. I have a tv and stand between the speakers and I cover them with dense foam to keep reflections from them to a minimum. I am going to run a test with no treatments and then add one treatment at a time and see what I get. I agree, the 2k dropout is a problem. I hear sounds clearly in my car that I can barely hear on my home system and I believe the sounds I’m talking about are in this range.

@bobpyle , unfortunately Bob, your ears do not a reference point make. You can not tell someone how to make their system sound like you want to hear. What is it that you want to hear? Well perhaps you like your system a little brighter. What does that mean. You can not say. 

None of this, except the way I tune my system to my taste is an opinion of mine. It is an approach that all serious professionals use. And you always start from a reference point and that reference point is a flat amplitude response across the entire audio spectrum. The technology to manage audio systems was not available to us back in the day. I got my first record player in 1958 and it had a tonearm that looked like a cobra and even had eyes painted on it!  Getting anything to sound right was a hit or miss proposition. People still behave as if this is still the case. It is not. With the right tools one can make almost any system (includes the room) sound good, maybe not great but in many instances surprisingly good. There are some rooms and situations that are totally hopeless but they are relatively few. The situations that are fantastic are also relatively rare, I am talking about rooms that were specifically designed for audio reproduction with speakers like your if you are a point source kind of guy or mine if you are into line source dipoles. 

You can never trust anyone's ears. People tend to like what they are use to listening to. To a person whose system is falsely bright a system that is correct will sound dull. If a person tells me he likes his treble advanced 3 dB/oct from 10kHz I know exactly what he means and can even imagine it. I can make almost any system sound the way I like without ever playing any music. If I analyzed your system I could tell you exactly what you are listening to, not my opinion of what you are listening to. 

@baclagg -- Good plan!  From your description, you may have too many things absorbing sound and one in particular that is taking out the 2KHz!  You can fix that with an equalizer. You can also replace your side absorber panels with a diffuser panel. You have all the tools you need at least.  Once you fix the 2KHz drop, you may find the system a bit bright. Most people prefer the output to slope down as the frequency increases.