I bought one subwoofer for a pair of model 812's to gain some extra bass, especially when used outdoor. I tried only once in a real environment (Covid party in the garden for my neighbours), it really rocks. It works very well and looks professional as the holder of the 812 top speaker, I am planning to invest more and buy a second one once the party season finally starts. What is surprising is the level of bass created from a relatively small sized box. It