@2、当L≠L2时,求L1+可查表(或查曲线见图 7-1)—分贝和的增值表 L,0 2 234567|8910 △L|3025211815121.0080.60.5040.3 步骤:(1先求L1与L2的差值:L1L2 (2)由所得得差值从表中查分别和得增值△L (3)由L1+=L1+△L,求出合成声压级值