This circuit can be used for coupling the audio output from your smarthone or “line out” from your PC into Arduino. This circuit will shift the signal between 0 and 5v.
You can leave out resistor R1 and capacitor C, but you need those two 100K resistors R2 as voltage divider.
Value of R2=100K is not critical.
You can use R2=68K or R2=82K as well.
But don’t use this circuit with coupling of output from power amplifiers, which could provide dozens of volt output power.
This is circuit is suitable for PC “line out” audio level or for audio output from your smartphone only, not for output from power amplifiers.
References
| Reference | URL |
|---|---|
| How to read data from audio jack? | https://forum.arduino.cc/t/how-to-read-data-from-audio-jack/458301 |
| Audio Jack Input In Arduino || AUX Cable || Analog Input | https://www.youtube.com/watch?v=Nxc_8gn1Vdg |
| *** ESP32 spectrum analyser VU meter using arduinoFFT and a FastLED matrix | https://www.youtube.com/watch?v=Mgh2WblO5_c |
| ESP32_FFT_VU - Code | https://github.com/s-marley/ESP32_FFT_VU |
| Max Sampling Rate of micro-controller code | https://github.com/s-marley/ESP32_FFT_VU/blob/master/Sample_test/Sample_test.ino |
Arduino Audio Input
| https://www.instructables.com/Arduino-Audio-Input/ |