Smaller vs larger listening rooms?

I go into a lot of different rooms for demos as the ATC importer. Every small room (including studios) have problems because they are too small. Small rooms do not have enough length or width to allow a true deep bass wavelength to exist in the room properly. If a 40Hz wavelength is 28.3 feet, how does that work in 20 foot room? It doesnt!.

On top of that it can be near impossible to get the speakers far enough away from the side walls to avoid overpowering 1st reflection problems. (this one can be easy to fix with acoustic material). It is shocking to me how many high end speaker companies do not know the 1st reflection issue is critical

I’d much rather do a demo in a larger room than a smaller one. A hotel room is impossible; a big hotel meeting room it starts to get better. Knowing that, the same rules apply to both rooms: don’t get near side walls (for good imaging), stay away from corners (boundary effects boost bass), avoid reflective walls and floors (wood/stone/ceramic floors, plaster walls, ceilings), stay on axis and in the triangle.

I think its usually easier in a bigger space. A good test of this is take your speakers outside in your driveway- WOW- do they sound different.
Brad