Vortekz

so im trying to get my 2 kam zp series 400 watts out and i have a gemini x3 amp which is supposed to be 600 watt. i have the jack leads connected to banana plugs by the amp but im not getting the bass. is this because im using a jack splitter into my laptop aux to test it? also does anybody know how much i can sll 2 of these for and a gemini x3 amp 2ndd hand? paid 250 for the amp like 5 years ago. not been used loads. cant find the x3 anywhere online