better volume change detection

I am currently using this microphone http://www.amazon.com/gp/product/B00BOM93VK/ref=oh_details_o08_s01_i00?ie=UTF8&psc=1 and have also tried this circuit http://www.instructables.com/id/Arduino-Audio-Input/

however it seems you have to be very close to the microphone for it to detect volume changes. I was hoping with a larger mic it would have higher resolution from farther away, but no luck. I have also tried adjusting the pot with no luck, it increases the threshold but not the sensitivity.

this was the sketch I was using for the UV meter:

#define NUMREADINGS 5 // Number of readings (increase for a slow curve)
#define MINSOUND 25   // Min sound intensity
#define MAXSOUND 125  // Max sound intensity
 
const int firstLED = 2;
const int lastLED = 9;
int leds;
int readings[NUMREADINGS];
int index = 0;
int total = 0;
int average = 0;
int sound = 0;
 
int x = 0;
int y = 0;
 
void setup() {
    for (int r = 0; r < NUMREADINGS; r++) {
        readings[r] = 0;
    }
    for (int p = firstLED; p <= lastLED; p++) {
        pinMode(p, OUTPUT);
    }
    leds = (lastLED - firstLED) + 1;
}
 
void loop() {
    total -= readings[index];
    readings[index] = analogRead(0);
    total += readings[index];
    index++;
 
    if (index >= NUMREADINGS) {
       index = 0;
    }
 
    average = abs((total / NUMREADINGS) - 338); // ((1024 * 300) / 1000) = ~338
    sound = map(average, MINSOUND, MAXSOUND, 0, leds);
 
    for (int ledON = firstLED; ledON < (firstLED + sound); ledON++) {
        digitalWrite(ledON, HIGH);
    }
 
    for (int ledOFF = (firstLED + sound); ledOFF <= lastLED; ledOFF++) {
        digitalWrite(ledOFF, LOW);
    }
 
    digitalWrite(10, HIGH);
    digitalWrite(11, HIGH);
}

I made a quick video to show what is happening too:

EDIT** (link updated): Dropbox - Error

any suggestions on what I might do to increase the sensitivity of the microphone?

dropbox link does not work :frowning:

oops, I just moved it, guess it doesn't like that.

you might need a logarithmic scale?

robtillaart:
you might need a logarithmic scale?

when I print out the output of the mic it makes me think its a problem with the sensitivity of the mic, or my setup. It's mostly that it doesn't change values with ambient sound, works fine up close.