Scrap, the situation is bad enough, now the idiots made them draw weapons. No choice here, got to give this little device its test.
Holding up the can like Device Mono pointed the hollow end with the modified speaker in the direction of the people with weapons. After a second he flick the Microphone, holding down the trigger causing the sound to become boosted by the parts below said Speaker. After a second a rather loud pitch (Breaking 130dB) Would have been emitted in the direction of the men, because the flick made little noise the returned sound was rather mute as the sound wave langht being reverberated inside the can became heavier and heavier till it left audible range.
"Cover your ears, not like it will help any. Sound this deep more or less penetrates the body."
"There will be no further conversation with the prisoners. Come quietly and no one gets hurt."
One could hear a few swords being drawn.