Parseval

例句：

1. 1.The sound of the piano reached a Parseval level.
   钢琴的声音达到了帕塞尔瓦尔级别。
2. 2.The speaker's voice was barely above the Parseval threshold.
   演讲者的嗓音几乎低于帕塞尔瓦尔阈值。
3. 3.The music festival had a grand finale with a Parseval performance by the orchestra.
   音乐节以一场由管弦乐队带来的帕塞尔瓦尔演出的盛大终场表演而告终。