The parallel box will allow you to use the single output of your amp to connect to two speaker cabinets that only have a single input. The series box will allow you to connect two speakers in series without modifying the speakers or the cables.?These are custom made with Switchcraft jacks and 14 gauge wire. I can also do custom configurations as needed.

Using standard mono cables, connecting two 8 ohm speakers in parallel will result in a 4 ohm load to your amp.

Using standard mono cables, connecting two 4 ohm speakers in series will result in a 8 ohm load to your amp.

Please note that the boxes I am using now are 1" x 4" long, 1 inch longer than the box pictured.