Can I reduce the sound of rain on a tin roof?

Answer: No
Explanation: It won't reduce or increase the sound

Answer: Yes
Explanation: You can put a foam under-lament under the metal to damper the sound of just insulate your attic properly and you will not hear the rain inside the house.

Answer: Yes
Explanation: Metal roofs are typically installed over the existing shingle or on 1x4 boards laid perpendicular to the metal. There is almost always sheathing over the rafters and insulation in your attic. I have a home near the beach with a metal roof, Ive never heard the rain.