One of my oldest friends, a drummer, has had a 4x12 cab that he’s pretty sure is an early 70s bassman 100. We both love it. My silverface champ sounded like a monster through it. Anyway, does anyone know what kind of speakers these came with? He’s pretty handy (a lot more handy than I am) and he’s never been able to get the baffle out for fear of breaking it. He says most of the cabs were either 10s or 15s, but this is 4x12, in a diamond shape, all angled towards the center.