In most cases it is a combination of what is available in the material and the capability of the speakers in your system to reproduce the sound. Many of us have speakers which go down to the 30-40 hz range but require a lot of power to do so. Many of us also have subwoofers dedicated to just those frequencies so we can supply more power to the mains at frequencies above the crossover. If I were in your shoes I would check the capabilities of your speakers and adjust your crossover such that it kicks in just slightly above the lowest range for your mains and let the subwoofer do the rest above the crossover point. Remember that although the 2150 comes with bass and treble adjustments it is set up originally for neutral use and to accurately reproduce the material being played. I would not expect you to have to crank the bass controls way up to get good response. Perhaps you got a defective unit or perhaps you are a bassaholic and need a bigger fix.