Exactly. You can hear bass in headphones quite OK, but that's a completely different experience from hearing the actual waves in a space where they have room to function...proper low bass will literally cause your heart to try to adjust to its beat...in headphones it's just a faximile...you know this of course from how in a large space a real strong bass will make you literally weak in the knees, even in an orchestra concert...thus any proper mastering studio will be deep enough to allow for true bass reproduction. And yes, the bouncing waves have everything to do with it, it's a science on its own to adjust a room to portray true frequencies as they are...not an easy task.