I Built a Raspberry Pi to Listen to My Coffee Roaster

VIDEO 2 — I Built a Raspberry Pi to Listen to My Coffee Roaster I could not always hear first crack on my Gene Café CBR-301, so I built a small Raspberry Pi device to listen to the roast for me. This is where RoastSignal began. Home coffee roasting on a Gene Café is loud. Fan noise, the drum, beans tumbling and the chaff wiper all peak at exactly the moment first crack matters most. In this video I walk through the whole journey: why first crack is the one moment that belongs to the coffee rather than the machine, why noise-cancelling headphones were a dead end, how a simple field recorder proved the signal was really there, and how all of that turned into a Raspberry Pi build with a screen, buttons and roast markers. Along the way the project quietly changed from a hearing problem into a timing problem, and the idea of a second clock appeared: a development timer that starts at first crack instead of at the very beginning of the roast. RoastSignal is a roast companion, not a roast replacement. The box listens. I still make the final call, and the cup always gets the final vote. WHAT THIS VIDEO COVERS Why first crack is so hard to hear on a Gene Café CBR-301 What roaster data can and cannot tell you about the bean Using a field recorder to confirm first crack is detectable Building a Raspberry Pi listener for home coffee roasting Why development time, measured from first crack, matters more than total roast time CHAPTERS 0:00 Introduction 0:06 The problem: I could not always hear first crack 1:14 What first crack is, and what the machine cannot tell me 2:27 Attempt one: noise-cancelling headphones 3:05 Proof it was there: the field recorder 4:07 Enter the Raspberry Pi 4:47 A screen, buttons and roast markers 5:27 From a hearing problem to a timing problem 6:29 Mission-control creep 7:18 The aim: a companion, not an autopilot 7:55 What is coming next Part of an ongoing series documenting RoastSignal, a home-built tool that listens to a coffee roast and helps time the finish. More at oneroastatatime.com Subscribe for the rest of the build: @CoffeeOneRoastataTime Gear: Gene Café CBR-301 drum roaster, Raspberry Pi. #CoffeeRoasting #HomeRoasting #RaspberryPi #FirstCrack #GeneCafe #SpecialtyCoffee #CoffeeGeek