Seeking Consultant/Designer for Acoustic Treatment of Room

I built a dedicated audio room a little over a year ago that has a whole lot of plusses, but definitely needs some acoustical work to deal with some tonal artifacts.  I am looking for someone to help me diagnose the issues and then design treatment to address things.  Any 'Goners happy with a particular firm that worked on your rooms?  (I recall Rives Audio, but they no longer service home installations.)
Reach out to GIK Acoustics. They give great advice and have very cost effective products.
I agree with @erik_squires re GIK.  I've gotten good products and good guidance from them.

Even if you ultimately hire a consultant, the first step is to understand the underlying principles of room acoustics, speaker and listening position placement, etc.  Learning to use REW software to measure in room frequency responses, decay times, and identify early reflections was an eye opener and game changer for me.  It does take time and effort, which not everyone can dedicate, in which case it may make sense to hire a consultant to to the heavy lifting if you have the money.  But these services don't come cheap.  I've spent under 3K to treat reasonably well my 20 x 15 x 8 dedicated listening room, and can probably finish it for less than 4K total.   All of the companies that offer room treatment products have useful tutorials.  
jb, where do you live? How large is the room? Describe it for us.
Your system?
This is not magic. Many problems are predictable and can be dealt with inexpensively. 
The best advice is always going to come from someone who is not trying to sell you something and obviously has experience with the problem. 
You can find the problems and if the inexpensive solution (about $50) is not aesthetically adequate you can then go out and get decorative panels made and get exactly what you need.  
Sure.  I live in Minneapolis, my room is 22.5' x 14.75' x 7.75'.  I built it with double layers of 5/8" sheet rock and Green Glue applied in a sandwich, and used excellent acoustical isolation around all fixtures, sockets, etc. so there is very little bleed through of sound out of or into the room.  The room has very solid basement walls behind the sheet rock, and 4 window openings along one of the long sides, creating some asymmetry of reflection.  I am running TAD CR-1's along a short wall.  The rest of my system is listed extensively under my moniker at Audio Asylum (too lazy to repeat it here).

I will have to look into REW software and measurement approaches, because it is clear that I need to understand my room's properties better.
JB, I have some acoustic decorative panel, If you need, kindly visit website: