User:Snow Rise/Preservation/Level 7 sound experiment

Level 7 Sound Experiment

Some time in the last century a sound experiment was carried out using a large (wooden?) whistle structure (possibly in France). This was given the title "Level 7" following the sound frequency used (7 Hz). This was so powerful that it killed one person involved in the experiment.

Since I cannot find any reference to this on the internet I invite anyone who knows more to contribute to this article, and edit it as necessary.

G. Brewis