mic echo suppressors needed badly

Please, i would like to ask for a design for microphone echio suppressors. I hope it is a simple one and it really works. don't worry i can manage bout the PCB lay-out.

Thank you very much!!!

The microphone cannot make echo.
Echo coming always from environment (walls, e.t.c.) If somebody discover some electronic antiecho solution, no more need the expensive sound isolation for studios...