When I say hard rock, I am speaking more of Cream, Hendrix, Grand Funk Railroad, etc. Of course Cream could be called blues rock, Hendrix psychedelic rock, and Grand Funk garage rock. But except for maybe the Beatles, those were the kind of bands I was listening to, not Motown too much. Also, cover bands I was in played covers by all those bands quite a lot. I think what I was listening to would be considered mainstream music of the time. Now that I listen more than I play, I guess things have changed somewhat.