The original Roy Box had no ports,and was more square than rectangular,almost a cube. There used to be a guy in NZ that had a system of JBL S-4 looking boxes,he drove them with his own 3-way amplifiers. We used that system when I was there with Kenny Rogers and Dolly Parton. 1986,IIRC. We hung them on Clair aluminum bumpers that we brought with us. Outdoors,in the round.
Or was that Tasmania? Geez I'm old!