Being a honorary administrator of a local engineering colleage I have received complaints from faculty members regarding echo problem in class rooms. The class room exact size yet to know approx 22 metre x 12 metre. In centre of the room a roof column is there. Both side walls have two windows each exact size yet to know. Very soon I will post that also. To avoid echo what we could do in simple way. One Fm has suggested to hang a heavy curtain in the rear wall for trail. If it is ok he has asked me to cover the rear wall with some acoustic material for permanent solution. All Forum members help and suggestions are welcome. Thanks in advance. Cheers.