These B-15 units are indeed massive. I have two matching A-15 units that I purchased in the early 1970s. In past times I actually gigged with them on a weekly basis . In the 1970s I was able to fit them both in a VW BUG with the rear seat removed . I powered that bass rig with a SUNN 2000S and a Fender Dual Showman . I was a tad stronger in those days . I still have those speakers that currently reside in my basement studio ,and have them connected to a Bi amplified sound system . I am powering them with a Yamaha P 2200 power amplifier crossed over at 500 HZ with a Crown VFX2A active cross over .The top end are two Cerwin Vega 211R's and and two EV mid-range horns horn powered by an AB Systems series 200.