I'm making an electronic drum set with piezo sensors. Currently I have two issues. First, the piezo's are producing relatively small signals. When printing the digital values on the serial monitor, the highest values are in the 30s (on a scale to 1023 of course). The sensors are in parallel to a 1Mohm resistor (I copied this from a few other piezo projects I found online).
The other problem is that I'm getting multiple triggers from a single drum hit. I'm assuming this is because the arduino samples the piezo signal multiple times after a single drum hit because the fall time of the sensor is slow relative to the arduino loop time. Is this accurate?
Any ideas on fixing these issues?