by Bruce EderAnyone who doesnt have a clear image of the Classics IV can be forgiven — they went through so many shifts in personnel and sound (not to mention a name change after theyd started recording), they were little more than a name attached to some excellent (and very good-selling) records of the second half of the 1960s, without a personality or identity to grab onto easily. Although theyre considered a late-60s phenomenon, owing to the chronology of their hits, the group can trace its roots back to R&B harmony (i.e., doo wop) music of the late 50s. Detroit-born, Florida-raised Dennis Yost, who joined on drums and moved into the singers spot, came from a Jacksonville-area band called the Echoes; he was just old enough to remember 50s R&B when it was current and, among many other groups, loved the Five Satins; and in addition to playing the skins, he sometimes liked to sing when the calls came for a 50s number like In the Still o...