New attributes of seat dip attenuation

New measurements have been made on the low-frequency attenuation of an impulse excitation over-seating in an unoccupied concert hall and on scale model seats. Two new attributes of the phenomenon were found the attenuation varied over time and the width of the seating area was also important. Because of this, the underlying mechanism of the attenuation may be best understood in the time domain. A scheme for reducing the attenuation with floor-mounted resonant absorbers was evaluated practically, and it was found that this might be incorporated into a hall ventilation system. Large effects attributed to the attenuation were found in graphs of clarity, centre time and strength versus frequency in the concert hall