I just need help with the schematics of this project. I just want to make sure this is correct before I order the parts. I want to send bluetooth music to the esp and the esp will activate the transistor (and in effect the magnet) everytime the bass hits.
The MAGNET item in the schematic is a simple wire around a magnetic metal. The transistor is an NPN MOSFET.
The questions I have are: is anything out of place? Do I need something else? Do I need to start learning high pass and low pass filters? As well as, anything else you guys can think of that may be an issue.
An N-Channel MOSFET would go between the electromagnet ("Drain" of the MOSFET) and Ground ("Source" of the MOSFET). The output from the ESP32 would go to the "Gate" of the MOSFET. There should be a diode across the electromagnet to absorb the negative voltage pulse that happens every time you turn off the electromagnet.
The ADC cannot tolerate audio input directly from a line or speaker source, so look up how to interface audio to an Arduino (DC bias and capacitive coupling).
This is the critical bit (well, that and I'd recommend that you learn to draw proper schematics, but whatever...)
Assuming (?) you are streaming music to the ESP32 using A2DP, that just gives you track metadata and outputs audio. It won't do any kind of signal analysis. You could follow the audio output with a low pass filter but it would probably have to be a pretty sharp one to work well.
Also, why 4 speakers? What are the extra two connected to?
[edit]
Interesting. this person apparently added a signal processing chain to the A2DP callback functions to build an LED spectrum analyzer that works with streamed audio. Take a look: I think it's exactly what you need.
