Of Course, all of the solo R&B singers had bands behind them. Some were definite groups of individuals. The R&B combos had a huge impact on the development of the British Beat scene of the 1960s. I do make a disction between these R&B and other Doo-Wop bands.
Here are my favourites:
Contours
Coasters
Dominoes
Don and Dewey
Isley Brothers
Miracles
Clovers
Drifters
Valentinos
Clowns