Comment by js2

I'm going to venture to guess the pair of subwoofers cabinets on their side are being used as a table and aren't otherwise connected. The only amplifier in the photos doesn't have nearly enough power to drive them and it appears to be connected to a small pair of bookshelf speakers above it.

https://news.ycombinator.com/item?id=44358442

(There could be another amplifier somewhere out of view.)