1. Old: Doorknocker. New: Deliverer of rhythmic monologue over a musical background
Your answer:
2. Old: Nearly cylindrical fish. New: Hairstyle, short on top, long on back
3. Old: Scattered or sown abroad by hand, dispersed widely. New: Transmission on radio or TV
4. Old: small rodent. New: moveable computer device
5. Old: Tinker of earthenware. New: Street attacker