A MP3 streaming WiFi speaker for ESP8266 & ESP32 chips

During a recent pantomime production we were unable to get the internal building sound system working and had to come up with a cheap solution to pipe music into the dressing rooms. Cobbling together a Raspberry Pi with sound card, ffmpeg and node rmtp server we were able to stream live AAC audio to a couple of mobiles running VLC Player. However due to the limitations of running live streaming on a PI, poor WiFi in the building and the buffering lag of VLC we ended up with a stuttering live stream that could be upto 40 seconds behind depending on the numer of connections, which was difficult for the cast and callers.

Having a couple of node mcu ESP8266 12E development boards that were destined for some extra home automation, I decided to see if it was possible to make a WiFi speaker that would perform better than our previous solution. That was the basis for my first attempt ESP8266_WiFi_Speaker and after puchasing a Heltec WiFi Kit ESP32 with an onboard OLED display and having problems with wifi managers I decided to create a new wifi manager library WiFiConnect and convert my previous project to support both chips.

   * ESP8266 ESP-12E Development Board NodeMcu
   * 2x 4ohm 3W Loudspeaker
   * Mini 3W+3W DC 5V Audio Amplifier PAM8043
   * I2S PCM5102 DAC Decoder ( [ESP8266Audio by Earle F. Philhower, III](https://github.com/earlephilhower/ESP8266Audio)
                                does allow for no decoder, but I have not tried it. )
   * 0.96" I2C IIC Serial 128X64 White OLED LCD LED 

   First major component problem was figuring out the DAC connections
   to use with AudioOutputI2S in the [ESP8266Audio](https://github.com/earlephilhower/ESP8266Audio) library.  
   The configuration I finnally manages to get to work was:  
      > 3.3V from ESP8266 -> VCC, 33V, XMT  
      > GND from ESP8266 -> GND, FLT, DMP, FMT, SCL  
      > GPIO15 (D8,TXD2) from ESP8266 -> BCK  
      > GPIO3 (RX,RXD0) from ESP8266 -> DIN  
      > GPIO2 (D4, TXD1) from ESP8266 -> LCK  

    The 5V Audio Amplifier PAM8043 needs a lot of juice and I found that as mine has a potentiometer I needed
    to turn it fully down to be able to program or run the ESP when only connected by USB serial connection.
    Powering from a USB power adapter for normal use, I had no problems.

    * Heltec WiFi Kit ESP32 with an onboard 128x64 OLED display
    * 2x 4ohm 3W Loudspeaker
    * Mini 3W+3W DC 5V Audio Amplifier PAM8043

    As the ESP32 has 2 onboard DAC's I decided to use them rather than use another decoder.

Please check/review instructions and screenshots in the Wiki

• Using buffering for the stream can cause alot of buffer underruns causing alot of stutter.
• With newer libraries installed compared to the previous project I have been unable to get a stable connection using the ESP12E unless I set the IwIP Variant to IPv6 Higher Bandwidth.
• Powering off of a com port can cause issues unless the amplifier is turned right down or off for uploading and playing music at higher volumes.
• As I can't seem to get the project to compile in Travis CI for ESP8266 NodeMCU board, I have added precomiled binaries to the initial pre release v1.0.1 and hope to post instructions in the WiKi soon.

Due to the possibility of frequent IP changes of my Raspberry Pi server I have used WiFiConnect and its custom paramters. After trying lots of different configurations for the server mp3 encoding(ffmpeg,darkice) and distribution(icecast2,shoutcast), I have settled on using Icecast2 and DarkIce with the following Darkice configuration.

Many thanks to the authors and contibutors for the main libraries that made this project possible

• ArduinoJson 6.9.1 https://github.com/bblanchon/ArduinoJson.git or https://blog.benoitblanchon.fr
• ESP8266Audio 1.1.3 https://github.com/earlephilhower/ESP8266Audio
• ESP8266 and ESP32 Oled Driver for SSD1306 display 4.0.0 https://github.com/ThingPulse/esp8266-oled-ssd1306 (I use a modified version,see WiFiConnect)

Stuart Blair (smurf0969)