Surely the OP has resolved this, but for future reference to those finding this thread in search of an answer to a similar problem, here goes... The speaker-out push-connectors are not on the powered side of the amplifier. They are on the Hi-pass (filtered) side of the crossover. In order to get an amplified signal out you would need to put an already amplified signal in. It's a method of stripping the low frequencies (called Low-pass or LFE) from an already amplified signal and sending on the higher frequencies to the satellite speakers. You can use this method or you can use the rca preamp output from your receiver to send already filtered low frequency signal to your plate amplifier. That gives you the flexibility to use your SW with any kind of equipment. Many plate amplifiers in powered sub-woofers will give you the option to choose how you get signal to the amplifier. This choice is especially useful if you don't have an available speaker output on your receiver or your using equipment that doesn't have a sub-output. Don't do both! The amplified low frequency signal your plate amp produces comes from the printed-circuit-board (PCB) side of the amp. There should be a pair of wires or or marked solder points on the PCB side. Look for + and - or a pair of red and black wires.