For me, I think it was Cat Stevens doing his first two big hit albums Tillerman and then Firecat,back to back. I'm not sure. It's hard to recall that far back. There was so much to do about the latest reprise of an older invention, I believe they called it the 'DRAFT'.
The last half of the sixties were such a volitile era one could not escape from it even with music. Music then dutifully echoed those tumultuous times, underlining the undeniable and at times, woeful losses and literally crying out for positive changes in social reform and the political rank and file. There was much to say and it was said. The content then seemd more akin to delivering a message than to commercial ends, although commerce was in full force as many of the outspoken groups & artists came to grater prominence
and a fair amount of those one of a kind sorts left the stage forever, and well before their time.
So great was the outcry, so pitiful the change by contrast. Mores the pity. Music however made immense strides s the result, or maybe in spite of it all.