{"id":3675,"date":"2021-11-02T22:09:07","date_gmt":"2021-11-02T21:09:07","guid":{"rendered":"https:\/\/www.pschatzmann.ch\/home\/?p=3675"},"modified":"2024-08-21T16:03:50","modified_gmt":"2024-08-21T14:03:50","slug":"streaming-mp3-files-to-a-bluetooth-speaker","status":"publish","type":"post","link":"https:\/\/www.pschatzmann.ch\/home\/2021\/11\/02\/streaming-mp3-files-to-a-bluetooth-speaker\/","title":{"rendered":"Arduino: Streaming MP3 Files to a Bluetooth Speaker"},"content":{"rendered":"

In the last Blogs I presented
\n– A File Based Versatile MP3 Player<\/a>
\n– A Streaming MP3 Player<\/a>
\n– A Streaming AAC Player with Volume Control<\/a><\/p>\n

All these examples were using my Arduino Audio Tools Library<\/a>.<\/p>\n

In this final Blog about this topic, I will demonstrate how easy it is to adapt the Sketch from the first Blog and send the output to a Bluetooth Speaker<\/strong>. Here is the Arduino Sketch<\/strong> which will work with a ESP32 Microcontroller<\/strong>:<\/p>\n

#define USE_HELIX \n#define USE_A2DP\n#define USE_SDFAT\n\n#include \"AudioTools.h\"\n#include \"AudioA2DP.h\"\n#include \"AudioCodecs\/CodecMP3Helix.h\"\n\nusing namespace audio_tools;  \n\nconst char *startFilePath=\"\/\";\nconst char* ext=\"mp3\";\nAudioSourceSdFat source(startFilePath, ext);\nA2DPStream out = A2DPStream::instance();  \/\/ A2DP output - A2DPStream is a singleton!\nMP3DecoderHelix decoder;\nAudioPlayer player(source, out, decoder);\n\n\nvoid setup() {\n  Serial.begin(115200);\n  AudioLogger::instance().begin(Serial, AudioLogger::Warning);\n\n  \/\/ setup output - We send the output via A2DP to a \"LEXON MINO L\" Bluetooth Speaker\n  auto cfg = out.defaultConfig(TX_MODE);\n  cfg.name = \"LEXON MINO L\";\n  out.begin(cfg);\n\n  \/\/ setup player\n  player.setVolume(0.1);\n  player.begin();\n\n}\n\nvoid loop() {\n  player.copy();\n}\n\n<\/code><\/pre>\n
The only difference is that we use the A2DPStream class<\/a> as output and when we configure A2DP, we need to indicate the Bluetooth Speaker name.
\nFinally we limit the volume and set it to 0.1.<\/p>\n
Audio Format<\/h2>\n
The Helix decoder provides 2 channels with 16bit data usually at a sample rate of 44100 and this is exactly what is needed by A2DP!<\/p>\n
SD Card<\/h2>\n
Here is the information how to wire the SD card to the ESP32<\/p>\n\n\n\n\n\n\n\n\n\n\n
SD<\/th>\nESP32<\/th>\n<\/tr>\n<\/thead>\n
CS<\/td>\nVSPI-CS0 (GPIO 05)<\/td>\n<\/tr>\n
SCK<\/td>\nVSPI-CLK (GPIO 18)<\/td>\n<\/tr>\n
MOSI<\/td>\nVSPI-MOSI (GPIO 23)<\/td>\n<\/tr>\n
MISO<\/td>\nVSPI-MISO (GPIO 19)<\/td>\n<\/tr>\n
VCC<\/td>\nVIN (5V)<\/td>\n<\/tr>\n
GND<\/td>\nGND<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
\"SD\"<\/p>\n
Dependencies<\/h2>\n
You need to install the following libraries:<\/p>\n