Yeah... I am not taking my speakers outside to experiment anything. My speakers are placed the best way possible on the tiny desk I have in the room for now... I am going to get my longer L shaped glass desk from my mother's house... eventually, that will give me more room for everything... but mostly my instruments. I will look into some treatment behind the speakers, but I am not about to deck my entire office out with the stuff. For a recording booth maybe, but my office isn't exactly hidden away and it still needs to be atheistically pleasing. Either way I am pretty happy with the system for the price. My walls sound great.
Everyone sees things their own way. I'm not imposing anything on anyone; you're free to do what you like.
This was just an experiment for those who want to; when I mentioned outdoor speakers, it was especially for those who truly want to see what their pair of speakers are capable of with their direct sound, nothing more. No one is going to install their home studio or home theater speakers outdoors.
Just don't forget that there are quite a few things to do before buying a pair of speakers; this is just the icing on the cake once the road is built. This won't prevent you from listening to your speakers in a "bare" room; however, you'll get 30% of their full potential. So much the better if it still makes people happy. There are people who are less demanding, and I'm aware of that while respecting you.
I read that you plan to apply treatment behind your speakers:
=> Thin absorber panels (the shorter the thickness, the more SBIR will be present in the high frequencies, making them easier to treat) to combat the (significant) SBIR phenomenon. This only applies to the panels behind the speakers.
For the rest of the early reflection absorbers, get thicker panels.
Musically. My pleasure, just to answer your needs, however, there are quite a few things to do before all that... but that's not the point.
The best thing to know before anything else is the proportions, impedance of the walls of your room + length, width, height, symmetry, etc..
Unfortunately, most people aren't so lucky; most often, we build a custom room ourselves. With whatever means we have, haha.
I'm very demanding when it comes to acoustics, listener placement, knots, bellies, measurements, etc., because they're essential for those who want to fully enjoy their listen, whether in a cinema or studio. You don't need to know everything—that's impossible—just the important basics.
I bought a single JBL 308P MKII speaker for the moment, a few weeks ago, and I'm starting from scratch. I sold everything; they'll serve as measurement speakers in the meantime. (and listen futur)
I already build (anticipate) full-range corner bass traps (without absorbers; I'll buy and install them when the time comes).
Full-range corner bass traps are a must in any room. Please add a rigid faceplate to the edges of the bass trap or superchunks, with 1D (preferred) or 2D diffusers on top, to maintain the room's vibrancy.
"Build it yourself = save money"