Robin Newman, who does some wonderful stuff with Sonic Pi amongst other things, recently received his RasPiO ProHAT experimenter’s kit and set himself a project. The project involved taking the components from the kit and adding a couple of capacitors and creating an LED bar graph. He takes the analog stereo output from the Pi (generated by Sonic Pi), runs it through the MCP3008 chip supplied with the experimenter’s kit and then outputs sound levels on the LEDs. Great work, Robin. Read more on his blog, see a video below and look at the code here.