What specific element did some accounts suggest the Romans experimented with in very large halls for potential sound dampening?

Answer

Incorporating large basins of water.

Roman engineering adapted many Greek principles but also introduced their own experiments, particularly concerning noise management in large gathering places. Some historical accounts point toward the use of large basins or containers filled with water placed within these expansive halls. The exact function remains debated—whether it was physical absorption due to the water's density and surface tension, or perhaps an incidental effect related to resonance—but it demonstrates an early recognition that introducing specific, heavy elements like water could alter the sound energy dynamics within an enclosed space.

What specific element did some accounts suggest the Romans experimented with in very large halls for potential sound dampening?
inventornoise controlsoundproofinginsulationacoustic insulation