The following circuit is the combination of echo chamber circuit that will make the sound repeated, just like an echo sound when you speak in cave. And the robot voice effect circuit that change the audio signal from input to become sound like a robot voice. Four pieces of 8 legs ICs used to build this echo chamber circuit.
To make the robot voice effect, there are some components need to be change.
Here some components need to replace for robot sound effect:
- R6 should be remove from the circuit
- R15, replace with 39K resistor
- R16, replace with 6.8K resistor
- C14, replace with 15-20pF nonpolar capacitor
- Adjust VR1, VR2 and VR3 to get the robot sound effect as you like.
Good luck 🙂