Tom, would any of these work?
http://velodyne.com/shop/subwoofers.htmlThe instruction manual for the High pass crossover switch
"This switch selects the frequency for the high pass crossover. This crossover is functional on both line and speaker-level outputs. Smaller
speakers with limited low frequency output may perform better using the higher 100 Hz setting that will reduce the low frequencies sent
to them. Larger speakers with greater low frequency output may be able to handle the 80 Hz setting without strain."
