EspAudioSensor
Jump to navigation
Jump to search
| Project ESP audio sensor | |
|---|---|
| File:NoPicture.jpg | |
| ESP-based audio sensor | |
| Status | Initializing |
| Contact | bertrik |
| Last Update | 2019-04-14 |
Introduction
This project is about using an ESP-32 together with an I2S digital microphone to create an audio sensor.
This could be a decibel meter, or perhaps an environmental noise meter.
A-weighting
Audio levels are generally measured in dB using the A-weighted scale. A-weighting calculates a subjective loudness level from a physical loudness.
Energy it calculated per octave and an A-weight factor is applied. In decibels this means adding a octave-specific number to the loudness.
Hardware
The physical device consists of:
- an ESP32 (or possibly an ESP8266), it has an I2S digital audio input.
- a digital I2S microphone, like the INMP441 (datasheet)
The microphone is connected as follows:
- INMP441 GND to ESP32 GND
- INMP441 VDD to ESP32 3.3V
- INMP441 SD to ESP32 A4/32
- INMP441 SCK to ESP32 A16/14
- INMP441 WS to ESP32 15
- INMP441 L/R to ESP32 GND
Software
Initial code can be found on github.
See also: