Can you hear Second Crack?


I have often seen people crib about not being able to hear First Crack. Some have improvised stethoscopes for it. Coming to the Second Crack since most appear to drop before it, I wonder if anyone who does roast to it and beyond has actually managed to hear it?

I, for one, am unable to hear it.


I just got my Bullet from this last wave in April and am just getting around to using it and doing my initial seasoning roasts. I’m still working out a permanent home for it, so for the time being I’m roasting outside where there’s slight road noise.

Since I’m seasoning, I’m charring beans past 2nd crack, and I can actually hear 2nd crack better than 1st crack - but I find both cracks hard to hear until they start to get rolling. That is to say, trying to hear when both cracks “start” is proving difficult so far. The type of bean probably plays a role, too - some beans are quieter than others.

Can’t wait to get my bullet set up indoors… hoping that will help me being able to hear stuff…


A few thoughts…

I don’t have a stethoscope. At around the time I expect 2C I tip the bean chute cover sideways so the underside of the cover reflects sound toward my ear. Works fairly well for 2C; works very well for 1C.

Decaf is very quiet at 2C, but that’s how it is. I have to depend on temperatures and do my best confirm that it’s going on. I usually miss the start of 2C with decaf.

And I have hearing aids which may or may not help since they amplify stuff I don’t want to hear (like the beans tumbling in the drum) as well as the good stuff.

One last one: if you see a few small circular chips falling into the cooling tray during the roast (about 1/8" dia.), 2C is already going on. They don’t always show up on the tray surface but if I hit 2C I almost always find them beneath the cooling tray when I vacuum chaff if I look closely.