Questlove's drums

ok so i was watching Late night with jimmy fallon and i saw that it looked like he had a snare in front of his bass drum, just wanted to know what it was

[Steady Freddy]

It's probably a Yamaha Sub Kick. It's a speaker that works like a microphone mounted inside a drum shell. It's for bringing out low end.

so thats a microphone?

Yeah, it's basically a re-wired speaker cone that acts as a sub bass microphone. This is the same trick that The Beatles used for many of McCartney's bass tracks. They discovered that using a very large diaphragm brought out the very lowest frequencies.