Help pzzzzzz

Sound in an empty room can be very loud,with many echoes.Describe three ways to make the room quieter?

2 answers

carpeting
acoustic ceiling

http://www.google.com/#q=make+room+quieter
Flat , perpendicular hard walls, ceilings and floors are a no-no.
Use heavy carpets, hanging heavy fabric, and soft ceiling tile.

Break up the flat perpendicular surfaces with nooks and crannies and odd angles and big furniture.

Use soft seating in an auditorium.

You can get high tech and design electronics to send out waves out of phase with the reflected waves