1: Keep back a missing ingredient for gunpowder (5)
4: Gershwin's retirement account? (3)
6: Vicar regularly outdated technology (1.1.1.)
7: Abundant specimen doffing cap (5)
8: Ninth-inning heroics on one side or the other (9)
11: King John's last to find out (5)
15: Makes empty noises behind listener. (5)