GIZMODO (GIZMODO, Gizmodo, gizmodo, gizmod, gizmo, giz...)! Or at least, that's what we'd have recorded, anyway.
But no, researchers including Trevor Cox, Professor of Acoustic Engineering at the University of Salford, instead chose a more conventional Very Loud Bang© to measure the acoustic properties of the Inchindown oil tank storage network near Invergordon. A gunshot fired within the bomb-proof World War II-era underground fuel depot resonated for a full 112 seconds before fading away, totally trouncing the previous 15-second echo world record. Even the slightly more conservative broadband reverberation reading (which covers all frequencies simultaneously, and is used as an official record parameter by Guinness World Records) lasted 75 seconds.
"It was like going underground into a Bond villain's lair. But never before had I heard such a rush of echoes and reverberation," Prof Cox told the Independent, describing the 9m wide, 13.5 metre long tanks, each twice as long as a football pitch. "I started off just playing around, whooping and hollering. The sound just goes on and on and on."
"Then when we fired the pistol my initial reaction was disbelief; the reverberation times were just too long. I knew immediately we had a new world record."
Have a listen to the resulting echo embedded below:
Also, make sure to check out some of the SoundCloud comments along the playback wavelength -- some of them are priceless. [Independent]