I pulled out the Ace Bass B2-50 for someone today and connected it to what I had lying around. A pair of budget Audex speakers (circa 1960) and a Pioneer SX-1250 receiver. I turned out be quite a good demo, mainly because the small 6-8" woofers in the 2-way Audex speakers are quite bass shy, giving the superb B2-50 lots of room to shine. Of course, the SX-1250 was an excellent performer (as always) with 160 watts on tap into these 8 ohm speakers. I've never seen a receiver pull in so many FM stations in stereo without an antenna connected.
Some details on the AudioPro Ace Bass. Its a powered subwoofer produced by 3dGruppen of Sweden and utilizes two 6.5" drivers made by Philips capable of doing 20Hz at realistic listening levels. It does great for audio, where many modern subwoofers fall flat.
A few more shots after the break.