Various diagram

The following diagram is the schematic diagram of echo chamber schema which will convert the sound of input to have echo sound like repeating sound if you talking in a cave. It will smoothing your sound also.
The schema based 4 main ICs that are a MN3005, a MN3101, and 4 pieces of AN6551. Ive made this kind of schema, its working great and you dont have to spend a lot of cost. :)