I am having a problem boosting the 40HZ to 80 HZ range on the EP500 when playing music. Since the new design has no trim control (replaced with subsonic filter)I need advice on how I can boost that range. Everything I tried so far seems to boost the low end then it sounds like too much bass. The R772 does have a parametric equilizer but I have it off. It has 5 equilizer bands were you can increase the dB will this solve it?