Hi I’m completely new to calibrating my home theater system using REW. I just got dual subs and calibrated it using a spl meter but heard to really get my speakers and subs as close as possible to each it’s better to use REW. I’m gonna buy a UMIK-1 and use HDMI on a laptop but I was wondering where to even begin with REW? Also do I need anything more to help me calibrate everything as close as possibe? I heard people get sound cards what are they used for and are they worth getting? I also was wondering if by rule of thumb you should measure both subs lower say 72 dbs so the combined output of both subs are 75db? Or is it better to level both subs at 75 dbs? Thank I’m totally new to this and to here haha!!!