I'm with you, when it comes to my favorite era. But 68-77 covers a lot of territory, sound wise. Up until at probably '71, most of Phil's sound was coming from his Fender/Sunn rig without PA support. At least, that's how it went down in places like the Fillmore. So, that would have been about 350 watts and 8 JBL 15s carrying the whole room. I can't imagine that it was as dominating at is was from the Wall on. But, I didn't see any shows prior to '76. I wouldn't say the shows I saw in the 70s had dominating bass. In fact, by the late 70s, it seemed like the bass was noticeably quieter than I would have liked. It was there if I listened for it, but it wasn't what I would call visceral. The clearest, biggest bass I heard, from '76-94, was outdoors in '88. Oxford Plains.