Former 70s boy band Bay City Rollers have announced a reunion, nearly 30 years after splitting up. http://www.bbc.co.uk/news/entertainment-arts-34323112 Yacontcha!
The 'Former' is superfluous here. Your use of '70s' locks them in to a more specific point in history.
BCR were an excellent band and I will be dusting off my Tartan baggies to wear them with pride, at the reunion concert...... Now ****in shoot me.