LEAF is capable of generating more than 154 decibels, the sound equivalent to standing next to several jets taking off. It is used to blast satellites and spacecraft with sound. Large horns are housed in a sound-proofed room that is 16.4metres tall. One wall of horns stands 11 m wide by 9 m deep and 16.4 m high. The nitrogen that's shot through the horns can produce a range of noise up to more than 154 decibels.
LEAF requires all the doors to be closed, operating in steel-reinforced concrete walls to contain the noise. The walls are coated with an epoxy resin to reflect noise, producing a uniform sound field within the chamber. The article doesn't say whether the knobs go past 11."
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