Audio Engineering

62 Chapter 2 2.18 System Gain Changes .......................................................................................... ...

Measurement 63 VU. The dBm and the VU are almost identical; the only difference is their usage. The instrument used to measure V ...

64 Chapter 2 movement in conjunction with a copper-oxide bridge-type rectifi er. The impedance of the instrument and rectifi er ...

Measurement 65 BLACK RED  3  3  2  2  1  1  (^10)  1  2  2 ^3 ^3 ^5 ^5 ^7 ^7 ^10 ^10 ^20 ^20 0 0 20 20 40 40 ...

66 Chapter 2 o r True VU level Instrument indication Zact  10 600 log ⎛ ⎝ ⎜⎜ ⎜⎜ ⎞ ⎠ ⎟⎟ ⎟⎟⎟ where, apparent level  instrument ...

Measurement 67 2.19.3 Calibrating a VI Instrument The instrument should be calibrated to read a true level of zero VU when an in ...

68 Chapter 2 2.19.4 Reading Apparent VU Levels Volume indicator instruments can be used to read apparent or relative levels. If, ...

Measurement 69 o r In. .HF In. .LF In 10 (xdecades .) (2.44) Further, HF..e()()xLFdecades In^10 In.. (2.45) a n d LF.. ...

70 Chapter 2 o r D cm f LP  ^ 39 10 3 0 0002.^1010 ⎛ ⎝ ⎜⎜ ⎜⎜ ⎜ ⎞ ⎠ ⎟⎟ ⎟⎟ ⎟⎟ (2.48) where Din is the displacement in inches ...

Measurement 71 For example, suppose that within the same critical band we have two tones each at 70 phons. Using Eq. (2-53), PT ...

Lower limit of organ scale Upper limit of ordinary piano scale Upper limit of concert piano scale 20 40 60 100 500 1k 2k 5k 10k^ ...

Measurement 73 2.23 The Tempered Scale ......................................................................................... ...

74 Chapter 2 The second method is more useful. It uses a tunable wave analyzer. This instrument allows measurement of the amplit ...

Measurement 75 2.25.1 Calculating the Maximum Allowable Total Harmonic Distortion in an Arena Sound System The most diffi cult p ...

76 Chapter 2 2.26 Playback Systems in Studios .................................................................................. ...

Measurement 77 For a harmonic to be equal to  33 dB, its percentage would be 100 10 2 24 2033   .%. For a harmonic to be ...

78 Chapter 2 out how many dB down each harmonic is compared to the fundamental, sum up all the harmonics and then compare their ...

Measurement 79 would be a 24-dB difference in level between these two loudspeakers when fed by the same signal. Some consumer ma ...

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Acoustic Environment Don Davis and Eugene Patronis 3.1 The Acoustic Environment ................................................ ...