Categories: Fun CircuitsMisc

Sound Activated Switch

This is a sound activated switch circuit. It’s will turn on and turn off based on a loud sound such as clapping your hands. You can adjust the sensitivity (how loud of a sound will activate the circuit) from a pin drop to a Mack Truck Horn. Very practical for a variety of projects. Add a relay to turn on a light when your dog barks, or set of a siren when an intruder makes a loud noise.

Here the circuit diagram:

This circuit operates on 9 VDC battery or you may use a DC power supply instead of a battery. Electret microphone used to catch the sound (very sensitive). The sensitivity can be adjusted via potentiometer.

Components List:

R1, R5, R16 = 10kΩ
R3 = 22kΩ
R2, R6, R9, R13 = 220kΩ
R4, R10, R12, R14 = 100kΩ
R7 = 270kΩ
R8 = 4.7MΩ
R11 = 1MΩ
R15 = 330kΩ
R17 = 4.7kΩ
P1 100kΩ Trim Pot
C1, C3 = 10nF
C2, C4 = 100nF
C5, C6, C8, C9 = 1nF
C7 = 1uF/16V Electrolytic
C10 = 100uF/16V Electrolytic
Q1 = 2N3904
Q2 = MPS6531
U2 = 4001 Integrated Circuit
U1 4011 Integrated Circuit
LED = LED Red
MIC = Electret Microphone

PCB Layout:

Download the manual instruction for this sound activated switch circuit:


This circuit kit available at http://www.electronickits.com/kit/complete/elec/ck1607.htm, go to that page to buy the kit.
circuit diagram

View Comments

  • Sir,,Is there any circuit diagram u know..that can turns the house light on when c clap sound is appears n remains constant..n also turns d light off with any sound or a clap..If u know about dis then plezz make for me circuit diagram for me..N send it to my e-mail d...plezzzzz sir

  • i would like to enhance some of its characteristics by installing voice regonisition and multi voice commands to activate light , fan ,ac etc.i would like to have some suggestions and propose circuit . iwill be highly thakful for ur help!!!!!!!!!!!!!

  • i want to do the clap activated switch but i donk know the procedure .!
    pls .help for my project .. thanksx .!

  • this circuit has a problem as you can't use any tv or audio system which may trigger the circuit. i was looking for voice controled triggering circuit

  • I want to build this Sound Activated Switch but I need to understand its operation. Please send to me more information about this circuit. Thank You!

  • The diagram is too fuzzy for me to read properly.I would really like to try to build this sound switch.

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