Amplifier: TL081 Comparator: TL081 or CA3140
R can be almost any value greater than about 10k. Use a small (low impedance) loudspeaker as a microphone
This circuit must have a 5v regulated supply. This is provided by the 7805 regulator.
The circuit shown above should be sensitive enough to respond to a reasonably loud clap of the hands at a distance of about a metre from the microphone. If the microphone (loudspeaker) is not very close to the circuit board, use screened lead to connect it to the rest of the circuit. If you require greater sensitivity, you can add the simple pre-amp shown below.