When I got my cab brand new, I broke in the speakers by snatching all of my mother's gigantic, over-sized bed and couch pillows and stuffing them in front of and around the cab.
Then I dimed every knob on the head and played for like two hours. Then when I got tired, I ran my MP3 player in to it for a few hours. Then I played my guitars through it again some time later.
And repeated for a few days 8)
Though you could kinda feel the bass in the floor, the sound didn't really bother anyone too much during the normal day...