I want to create a circuit that can detect audio frequencies and flash RGB LEDs different colors depending on the detected frequency. The frequency range will be from 20 Hz to 12 kHz, after looking at the chart below.
So my question is: what circuit design should I choose to make a good frequency detector? I suppose I would need
- Preamp for the microphone (is it necessary for the ADC?)
- Band pass filters (active or passive?)
- A microcontroller with an onboard ADC that has a sampling rate of at least 24 kHz.
Before I get too excited, are there any circuits out there that already do this?