Room acoustics how ? My image is not centered


The sound of my system is not good. the image is tending a bit to the left and not centered, the sound is "hard" and there is no much stage.

I own Merlin MMe, VAC Avatar super, Electrocompaniet EMC1 CPD, cables: audience au24, cardas golden reference

as for the unbalanced, I tried all the combination's of switching cables sides and every time the sounds is bit stronger on the left. so I suspect my problem is with the room acoustics. the left wall is made of concrete bricks and the right wall is all glass-fronted (maybe this is the cause?) the ceiling is made of wood.
do you know how can I scientifically measure and check the sound in my room ? and scientifically found the places where I need to put some materials for better acoustics ?
any good info and/or reference for web site explaining on room acoustics ?

about my amplification (VAC AVATAR SUPER), I suspect (only syspect) its really not match the Merlins since the sound is bright and "hard". anyone have experience with it with the Merlins ? better suggestions for amp or pre& for the merlins ? (for used price ~5500$)

thanks
128x128haimschindler
Paulsax, I copied the instructions from one of the Audio Circle posts. Send me an email and I will send you a copy.
thank you all for your advices!
the main problem with my system was probably beyond what a bad room acoustics can cause. some time after I bought the VAC super I changed and altered some of the tubes and stayed with it.
well, I now put back my original VAC tubes (4 KT88, 5 12AU7, 1 12AX7) and I put them in their RIGHT order after consulting VAC. each KT88 I put in its right socket number (I had never notice the socket number is written on the tubes) and the two golden dragon 12AU7 had to be in the edges and not anywhere else.
the sound now become so better as it should be from a hi-end system! yes, still there are some problems with room acoustics and I am going to try and fix it but the sound is so good and balanced now...
just before I found my problem I ordered the filarmonia amp from ars-sonum spain. merlin and some reviews claims its a very good match with the merlins so maybe after I get it the sound will be more better...
anyone can explain why the KT88 tube where numbered to their sockets ? is it because tubes "matching" ?
A WAG. Not enuf info to tell for sure, but my guess is that the tubes were biased by VAC when they had possession of the amp and the tubes were in the correspondingly numbered sockets. ARC always does this for example when the amp is sold new or it is returned to them for tube replacement.