@erik_squires, I like both of your ideas.
Many years ago there was a company called Audio Concepts who sold to the DIY speaker builder market. They competed with Madisound and Parts Express and Meniscus. Anyway one of their kits was a medium-sized floorstander whose outer surfaces were covered with 2" thick egg-crate foam, with cut-outs for the drivers. Allegedly it imaged very well. I never went to that extreme, but admired their design for its no-holds-barred devotion to eliminating enclosure reflections and diffraction. Your removable curtain/blanket approach has a MUCH higher WAF!
As a longtime dipole enthusiast, I’ve often added weight to the top of a dipole speaker. The idea being, a dipole speaker is seldom perfectly rigid and free from rocking, so it can be thought of as an upside-down pendulum. Adding mass to the end of the pendulum (the top of the dipole in this case) lowers its natural rocking frequency, making it less prone to rocking at audio frequencies. Improvement shows up in imaging and bass response, but in my experience it’s usually not a huge improvement.
Duke
