The SoundDuino Arduino sound shield is capable of working with voltages from 3.3v to 5v and if you use the other Arduino boards, the only pins that you require are GND, VCC, RX, TX.

This effort will provide developers with compatible libraries via the official Arduino Library Manager in Arduino Create as well as the Desktop IDE, and further comprehensive documentation, tutorials ...

We have seen a few that use the Fast Fourier Transform to map the audio signal on the display as this one does. But [Phil’s] choice of an assembly language Library for ATmega chips makes this ...