In the extremely cool demonstration video Demonstration of Acceleration Inside the International Space Station During a Reboost ISS Expedition 22 Commander Jeffry Williams says near the end at
04:48 that he could hear that the boost burn was complete.
I am not sure which engine was used for these burns in 2010, but how does it manage to make enough noise throughout the ISS to be heard over the drone of the ventilation system and all of the other equipment?
I here a faint "ping-pong" (sounds like the 7-11 automatic doors where I live) just before Williams speaks, but I'm assuming that's a video camera being turned off.
video cued at