Sound transmission through double leaf lightweight partitions part I: airborne sound

Statistical energy analysis (SEA) is used to model sound transmission throu gh double leaf lightweight partitions. It is found that the best SEA model depends on the frequency range considered and the method of construction. A t low frequencies the wall can be modelled as a single subsystem while at h igher frequencies it should be modelled as a number of interconnected subsy stems. The structural connection between the two panels can be modelled eit her as a series of independent points or as a line connection, depending on the nail spacing. The results show that the basic SEA model is appropriate for this type of structure and that structural coupling can be accurately predicted. However, it was found that the theory for transmission into (and out of) large rooms cannot always be used with confidence to predict trans mission into (and out of) a cavity. The error in this transmission path can lead to large errors when predicting transmission through the complete dou ble wall if transmission is dominated by transmission paths involving the c avity. (C) 2000 Elsevier Science Ltd. All rights reserved.