Most sensitive analog sound / audio sensor

Other Hardware Sensors
1

Hey i was wondering if anyone could point me in the direction of the most sensitive analog sound / audio sensor, i have a high speed photography project that is working well but requires quite a knock / bang to trigger it when some subjects are very quiet in motion and do not trigger my arduino nano?!?

I currently have a standard piezo buzzer/sensor and not really noticing any difference wether i put a 10K resistor or a 240ohm across the input. Also i have set ---->

#define SENSOR_THRESHOLD 0 // Current Threshold

if ((mode == ACTIVE) && (analogRead(SENSOR) > SENSOR_THRESHOLD))

With either resistor if i drop a set of keys on the same table as the sensor it will fire every time but if i clap as loud as i can as close as i can it may fire 1 out of 10 times. In an ideal world i would like a sensor that is sensitive enough for me to have to be SILENT when my project is in ACTIVE mode and then up my resistors so a slightly louder pop / bang will trigger.

Any replies will be much apreciated
Thank you

2

Piezo devices can be very narrow banded. Have you looked around for any op-amp circuits that will amplify sound for you? You can do allot with them, including making active filters to pick the frequency range you are interested in.