ECHOES museum

In a square room of Ujazdow Castle, Warszawa, with walls, floor & Ceiling made of smooth stone, & (important detail) the top of the walls a little rounded to join the ceiling, here are a few basic exercices of « barehand acoustics ». With fingers snapping, hands clapings & steps taping one can reveal the reverberation & the floating echoe from the center point of the room. With the voice speaking & then singing, one can find its resonnance frequency (around 320Hz here), & almost measure its size by the ear...