I'm actually worried about tone rather than volume. The wife doesn't care much when I play, but I don't have much reason to play very loud. But if you're playing low, what's the best you can do for your decibels? Ported design for more bottom end? Larger box for resonance? Deeper box? Closed, open? There must be a huge market of guys out there in apartments and basements who can't or don't need to crank it up loud. Maybe design doesn't make a difference, of course.