@treidag
A simple test CD , available on line will play the range of frequencies, test separation and a bunch of other prameters of you system. A sound pressure meter can be had very cheap( it’s good to use to monitor power equipment too) These simple tools are eye openers as far as room influence is concerned. They are fun and informative to use, especially analyzing your instruments in a room or theater.
Just moving a speaker a few feet can make a huge difference in it’s over all response. Some think that changes the sound of the speaker. It doesn’t. It changes what you hear while speaker is still producing the same sound. . YOU moving around the room changes the sound you hear as well.
In a modern theater, the price difference between environmental sound control and the actual cost of the theater speakers, indicate how important a room is. The actual construction is with that in mind. When they make the theater, they are making the single most important part of the sound system.