Why do the BB15 and DJ18S have casters on the rear, while other subs have wheel carts?

If you're curious why some of our subs (like the BB15 and DJ18S) have the option to install rear casters, while most of our other subs have wheel carts, you've come to the right place!  Our larger subwoofers have wheel carts for the following reasons:

1. Putting bolts into the cabinet (for where the casters are) can create air leaks, especially if the casters are installed in place of the bolts.
   
2. Putting casters on the rear of the cabinet involves tipping the cabinet each time one wants to transport it.  The SSP118 has a very low center of gravity so it would involve applying quite a bit of torque/lift to flip it on the casters (the DJ18S and BB15 have higher centers of mass/gravity where tipping the cabinet is less difficult.  Plus both are lighter cabinets).  It simply does not make sense to put casters on the rear of the SSP118 for this reason.  This is even more apparent for our double-driver subs that weigh more.
   
3. Flipping the cabinet can wear the wood/finish on the edge that serves as the fulcrum for tipping.
   
4. The casters can (and often will) rattle when deeper bass notes are playing when they are attached to the rear of the sub.  This is not as much of a concern for the BB15, but the SSP118 gets quite a bit deeper where this can be problematic.  If the sub is sitting on the wheel cart (or the wheel cart is removed during operation), this will not be a problem.
   
5. The wheel carts allow one to transport and position several subs at a time, including entire cardioid stacks of SSP118s.  For larger productions this saves setup, load-in, and load-out time.  The DJ18S and BB15 cannot stack, while the SSP118 and our dual-driver subs have interlocking feet or sliders that allow for secure vertical stacking.
   
6. If using the wheel carts during operation, the wheel cart provides a bit of "lift" to the speaker so any drinks (or other fluids) on the ground do not touch the cabinet or get into the port as easily.
   

See Also:

1. SSP118 vs DJ18S - Which Is Right for Me?