For a first series of prototypes, the concept work has been focused on drum venting – which is a topic that leads still to intense questions in the drum building community.
From no air vent to rare « ported » drums, to many vents or huge cuts in the shells presenting many shapes, all having their influence on the sound, this subject has triggered some creativity.
The very idea of venting a drum is often answered by « this is done to allow the membrane to vibrate more freely, not being impeded by air compression inside the shell » – this leads in fact to a very complex subject of « Fluid/Structure interaction » to which the answer is most of the time provided in the « non acoustic » domain.
More in the Physics involved page.
Some of our prototypes :