Hao4K影音

宅嗨网振动论坛声学基础总结1声学基础方面推荐书籍南京大学出版社版，杜功焕编《声学基础》：海洋出版社版，周新祥编《噪声控制与应用实例》：机械工业出版社版，马大献编《噪声与振动控制工程手册》。宅嗨网2声音强弱与高低的区别对纯音来讲，强弱取决于声压的幅值，高低取决于频率：对混音来讲，强弱与高低相互影响，取决于频谱和人耳听觉特性。强弱用计权声级、响度来衡量，高低用尖锐度来衡量。3低中高频的一般划分500Hz以下叫低频：500-2000Hz叫中频：2000Hz以上叫高频。海网听阈声压20Pa(0dB),痛阀声压20Pa(120dB).5声级计算及其关系P声压级：Lp=201PPo宅嗨网声强级：L,=10W声功率级：网W=10-2W:宅嗨网400声强级与声压级的关系（自由场）：L,=Lp+10lgPoCo声功率级与声强级的关系（自由场或者半自由场，球面波）：Lw6声压级的加减两个相同声压级相加，总声压级=单个声压级+3B:N个相同声压级相加，总声压级=单个声压级+10lg(N):海网Addition of dB Levels宅嗨网dBExample:3宅嗨L 55 dBL2=51 dB△L=4dB21.4dBL55+1.4=56.4dB1.4dB嗨网051015dB嗨网4 dBDifference in dB(A)BetweenAmount in dB(A)to AddTwo Noise Levels Being Summedto the Higher Noise Level0to0.53.01.0to1.52.5海网2.0to3.02.03.5to4.51.55.0to7.01.07.5to12.00.50Noise levels should be summed in a pairwise fashion when Table 6 is used and the final totalrounded to the nearest whole dB(A),with values of 0.5 or more being rounded upwards.海网声压级相减的原理同声压级相加：Subtraction of dB LevelsEx:60 dB6△L=7dBL=1dB4宅嗨网Ls=60-1=59dB宅嗨网212345678910dB漏Ls~Ls+N宅嗨网7如何计算1/3倍频程宅嗨网宅嗨网宅嗨网中心频率：fm=1000×2B,x在1000Hz处取0，低于1000Hz递减1，高于1000Hz递增1：下、上限截止频率：fmf2-1719.717.522.1-1624.822.127.8-1531.327.835.1-1439.435.144.2-1349.644.255.7海网-1262.555.770.2-1178.770.288.4-1099.288.4111.4-9125.0111.4140.3-8157.5140.3176.8-7198.4176.8222.7-6250.0222.7280.6-5315.0280.6353.6-4396.9353.6445.4-3500.0445.4561.2-2630.0561.2707.1-1793.7707.1890.901000.0890.91122.511259.91122.51414.2海网21587.41414.21781.832000.01781.82244.942519.82244.92828.453174.82828.43563.664000.03563.64489.875039.74489.85656.986349.65656.97127.298000.07127.28979.71010079.48979.711313.71112699.211313.714254.41216000.014254.417959.41320158.717959.422627.48计权及计权声压级模拟人的听觉特征，对不同频率的声压级予以增减计权，常用A计权，对应A计权声压级。0909-Relative001-response0OLI'LL-99-000'9I00S'ZLI'I-000800E9E'I-E'I+0009I0090+00080-00800E900080-99-SIE0E'I-00'E-I'6I-b'L-g'te-0880-E9E'L-9'LL-9'FE-t'6E-S'IE987-9I