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using a microphone as sensor

I have a couple of headset microphones, and I would like to use them as sound sensors..

I tried to amplify the signal using LM386, but it doens´t work.. can someone help me on this?

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Finally I have some time to continue with this investigation and great improvements were achieved with the circuit provided by Ant:  http://www.rev-ed.co.uk/docs/picaxe_sound.pdf

First here are the photos deleted by mistake from flickr:

Headsets microphones

3497277414_eff0b1d252.jpg?v=0

Electrec thingey inside.

3496461163_701fff777f.jpg?v=0

The circuit

3496460749_877a2af1b2.jpg?v=0

This is a closeup of the circuit, I´ve added a 10uF capacitor to stabilize the output signal (it´s the green cap on the right).

3496460969_d6f3e8e836.jpg?v=0

The problem here is that I can´t imagine myself soldering all this components onto a pcb, I would like to have at least two of these, four would be awesome.

Below is a video showing the data visualization and code for Arduino and Processing:

I don´t know why the video doesn´t show up.. here´s the link: http://www.flickr.com/photos/guibot/3497408152/ 



/* ****************************************************

Arduino Code

**************************************************** */ 

int analogValue;
int val;

void setup()
{
// start serial port at 9600 bps:
Serial.begin(9600);

}

void loop()
{
// read analog input
analogValue = analogRead(0);

// send values to processing
Serial.println(analogValue, DEC);

// pause for 10 milliseconds:
delay(10);

}

/* ****************************************************

Processing Code

**************************************************** */ 


// import the Processing serial library
import processing.serial.*;

// declare a font variable
PFont font48;

int linefeed = 10; // Linefeed in ASCII
Serial myPort; // The serial port

// value recieved from the serialport / arduino
int sensorValue;

// mapped value
float sensorValueMap;

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Setup

void setup() {
myPort = new Serial(this, Serial.list()[0], 9600);

// read bytes into a buffer until you get a linefeed (ASCII 10):
myPort.bufferUntil(linefeed);

size (800, 600);
background (0);
//smooth();

// you need to have this font in your machine, if not go to
// Tools - Creat Font - and create your own font
font48 = loadFont(”alask_48.vlw”);

textFont(font48);

}

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Serial Event

void serialEvent(Serial myPort) {
// read the serial buffer:
String myString = myPort.readStringUntil(linefeed);

// if you got any bytes other than the linefeed:
if (myString != null) {

myString = trim(myString);
//println(myString);
// split the string at the commas
// and convert the sections into integers:
int sensors[] = int(split(myString, ‘,’));

// print out the values you got:
for (int sensorNum = 0; sensorNum < sensors.length; sensorNum++) {
//print(”Sensor ” + sensorNum + “: ” + sensors[sensorNum] + “\n”);

// sensor
sensorValue = sensors[0];
//sensorValueSmooth = sensors[1];

}
}
}

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Draw

void draw() {

// set the black backgrounf
background(0);

// run the displayText() function
displayText();

// map the recieved values
sensorValueMap = map(sensorValue, 0, 1024, 0, 800);

// draw a rectangle based on the variable sensorValueMap
rect (0, 100, width, sensorValueMap);
}

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Display Text

void displayText() {

text(”Sensor Value”, 20, 80);
text(sensorValue, 450, 80);

}

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Save image

void keyPressed(){
if(key==’s’)
saveFrame(”sound-######.png”);
}