Arduino nano ble sense microphone

Help
#1

Hi everyone, I’m having issues trying to create a ML with the arduino nano ble sense…

I have successfully connected the board to edge impulse, and using the microphone at the frequency of 16000Hz. The issue is that the noise that I’m trying to sample, is over 100db, and when I sample it, I just get nothing from it, like a deaf sound… Is there any possibility to increase the sensibility of the board?

#2

Hi @ChristoMa here’s the datasheet for the microphone on the Arduino Nano 33 BLE Sense: https://content.arduino.cc/assets/Nano_BLE_Sense_mp34dt05-a.pdf

Here’s a nice tutorial I found that explains how you can increase the sensitivity of the microphone on the board with a MAX9814 Electret microphone amplifier: https://create.arduino.cc/projecthub/javagoza/sound-spectrum-visualizer-with-arduino-nano-33-ble-3c6261

#3

You can also manually change the PDM gain in the Edge Impulse SDK by following the instructions in the firmware for Arduino Nano 33 BLE Sense repo here: https://github.com/edgeimpulse/firmware-arduino-nano-33-ble-sense/#edge-impulse-firmware-for-arduino-nano-33-ble-sense

And associated microphone file: https://github.com/edgeimpulse/firmware-arduino-nano-33-ble-sense/blob/master/src/sensors/ei_microphone.cpp#L335