Sound Reacting Circuit in 2 Minutes

About: I am robotics engineer and a teacher whose passion in life is breaking down the maths and academic jargon of programming and robotics into something that everyone can understand, primary school kids include...

There are 1000's of ways that you can make LED's react to sound and this here is definitely one of the simplest with the added advantage of being easy to modify and upgrade

Basically you plonk a mic module into pins A0-A3 and a RGB LED module into pins 8-11 (see diagram) then you upload one of the programs below that do the following

Program 1: MIC_RGB

Calculates loudness by taking consecutive readings and minusing one from another. Then it lights up the LED module in the following manner

low loudness = blue

mid loudness = green

high loudness = red

Program 2: MIC_RGB Bonanza

Calculates loudness then assigns 4 different ranges of intensity as a sound reaction using the random number function see code below:

NOTE: range applies to all colours

if (absLoudness ==2) Range of intensity = 0 - 10

if (absLoudness ==3) Range of intensity = 10 - 30

if (absLoudness ==4) Range of intensity = 20 - 45

if (absLoudness > 4) Range of intensity = 130 - 255

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