Hello, I have installed my JL 12W0 today, have a box where two fit in but is now only one inside. the membrane swings already pretty hard but does not come over as much as I imagined. It is closed in about 42 L housing and is operated with an impulse SD520 2x185rms At that time I had an impulse CW1212 inside and it was much better, I had had had the he had 600rms. since I was there to unclean I bought the Jl Soon I will vi easy to buy a second JL and wanted to ask if that would bring a lot more?