I have 240 pounds speakers on iso acoustics. My solution is having them resting on a butcher block. Whether on hard surface of carpet, the butcher block can be moved by pushing or pulling it at the base accordingly. It will move even a 240 lb speaker, though it requires good hand strength.
Tweaking Your Speaker Placement
"Depending on the speakers an 1/8” move in the right way can have a significant impact."
What I am curious about is how one can verifiably move a speaker exactly 1/8th of an inch? My speakers on stands weigh about 60 pounds each and being bookshelf speakers, they are a little top heavy. They are also on IsoAcoustic Gaia's, which don't really slide too well.
How do you do it?