It’s true that in space no one can hear you scream. Blastoff, on the other hand, can make quite a racket, which is why engineers use the Acoustic Test Chamber. In this 42-foot-tall chamber, technicians expose payloads to the noise of a launch with the help of 6-foot-tall speakers.
The speakers (more accurately called horns) use an altering flow of gaseous nitrogen to produce a sound level as high as 150 decibels for two-minute tests. That’s about the level of sound heard standing next to a jet engine during takeoff.
The speakers are still audible -- at greatly reduced volume -- outside the chamber, even through the insulation of massive metal doors.