Control room acoustics problem

I'm very sure that most of the issues I'm having gettting a good distorted guitar tone recorded have more to do with my control room acoustics than anything else.  In my efforts to get a good recording I decided to try to emulate the tone of one of my favorites...Andy Timmons.  I imported one of my favorite Andy Timmons tracks into Sonar and immediately realized that the guitar didn't sound nearly as good as it does on my car stereo.  In fact, it has some of the same issues as my own recorded guitar tones.  I also notice that source coming from my left and right channels sounds like it should, however, the center channel sounds like it's coming from center BUT up.  In other words the center channel sounds like it's coming from where the front wall meets the ceiling instead of directly in front of me.  I actually have to tilt my head back and look up in order to look in the direction I'm hearing the center channel come from...(*note - my monitors are at head level and pointed toward the listening area forming a triangle).
 
So, I'm thinking I've got some wicked reflections bouncing around the control room that are causing this effect and may also be cancelling out some of the midrange my guitar seems to be missing.  I've got acoustic treatments in the control room, however, I put those us with no real knowledge of proper placement...mostly just around the listening area.  I've been doing a lot of reading about how to place acoustic treatments and I now intend to have someone move a mirror around on the walls and ceiling while I sit in the "listening" area and if I see the reflection of the monitors I will put some acoustic treatment on that area. 
 
Any thoughts?

the acoustic treatments will help - first reflections (the mirror trick) on the walls, ceiling, and consider the floor as well. then your back wall reflection. then scattered absorption as needed on walls and ceiling to break up the "flutter echoes" but not too much so your room is overly absorptive. the challenge is to get the room frequency and levels response right without making it worse by over absorbing HF or MF  = muddy...

Could it be that you're hearing it on studio monitors that are flatter than the car system which is not? 

Now... on the monitors, it's not that it sounds bad, it just doesn't sound as good because now you hear it like it really is. 

Possibly? 

Maybe I need to remove some of the acoustic "cocoon" that I've created around the listening area.

I wouldn't do that, at least not as the first step. In the end, maybe you really are absorbing too much in too narrow a bandwidth, but absorption behind the speakers is usually a good thing that you can't have too much of. More likely suspects are the walls to either side of the speakers and the ceiling (especially if it's low). Ideally, you'll want to place absorbers in all three locations, midway between you and the speakers and a few inches away from the walls/ceiling.


(This is all to control flutter echoes and comb filtering, which will help stereo imaging. Unfortunately, these measures will do nothing for low-frequency resonances. For that, you'd need real bass trapping, which is difficult and takes up a lot of space. But it's more likely your problem is in the midrange and upper-mids.)


Based on your description, it sounds as though you're experiencing phase cancellations between that portion of the signal that's common to both left and right channels. If the center sounds fuller with headphones, that would confirm the hypothesis. First, make sure your speakers are equidistant from the nearest walls. If one is closer to a wall than the other, that'll skew the panorama and do weird things to the center.