Recommendatios?

Large room (20 × 40 x 10). Audio at one end with speakers facing side wall.  Acoustic panels on all walls.  Have not done room correction.  Realize I can move up in the Wilson line but is there a better alternative?

Appreciate responses and suggestions, will take all under advisement.  Duke envisions correctly that speakers located at end of one long wall facing opposite long wall and only several feet from the side wall so there is a lot of asymmetry regarding speaker placement.  I believe I get decent imaging and sound stage  but not a lot to compare it to.  Could reorient speakers to face the length of the room but would block windows with nice view.   I do feel like there is a feeblenesss to the sound which may be related to room size and speaker placement.  Have only absorbers and no diffusers.  Did add an old 100 watt Velodyne 10 in. Sub parallel wired to speakers and that did make a very noticeable difference at the low end.  Maybe I just need more juice in the amp/speaker combo.

Help me out.  How do I measure/determine sound pressure level?

Spec sheet says 89 dB at 1 watt if that helps

Thanks for tip on Get Better Sound.  Will pick it up

You are correct.  The 200Dsi is a class D with 200 watts at 8 ohms and 300 at 4 ohms which I have assumed is enough juice.   You are also correct that high end sounds a little anemic.  Will take your advice and get some local expert input on getting the room right before moving on.  If that doesn't do it, do you have speaker/amp Recommendations? Thanks

The acoustic panels were installed yrs ago by reputable local audio dealer.  They are fabric-covered panels app 2 in. thick containing a synthetic foam.  If needed, can ck with original installer for more detail.