| Section 1. What is a Sound System |
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1 | (3) |
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1 | (1) |
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The electrical representation of sound |
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2 | (1) |
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2 | (1) |
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3 | (1) |
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The basic purpose of a sound system |
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4 | (1) |
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A conceptual model of a sound system |
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4 | (1) |
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5 | (1) |
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5 | (1) |
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A practical model of a sound system |
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6 | (3) |
| Section 2. Frequency Response |
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9 | (3) |
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Basic specification methods |
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10 | (1) |
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Octave relationships and measurements |
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11 | (1) |
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Frequency response of practical audio devices |
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12 | (3) |
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Electronic circuits and cables |
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12 | (2) |
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14 | (1) |
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14 | (1) |
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Voice and instrument ranges |
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15 | (2) |
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15 | (1) |
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The singing voice and musical instruments |
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15 | (1) |
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16 | (1) |
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Effect of acoustical factors |
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17 | (2) |
| Section 3. The Decibel, Sound Level, & Related Items |
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19 | (3) |
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A mathematical definition of the dB |
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19 | (2) |
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Relative versus absolute levels |
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21 | (1) |
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Relating the decibel to electrical signal levels |
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22 | (3) |
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22 | (1) |
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22 | (1) |
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23 | (1) |
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Converting dBv to dBu (or to dBm across 600 ohms) |
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24 | (1) |
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Relating dBv, dBu and dBm to specifications |
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24 | (1) |
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25 | (1) |
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Relating the decibel to acoustic levels |
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25 | (2) |
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25 | (1) |
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26 | (1) |
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27 | (1) |
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28 | (1) |
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29 | (4) |
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Equal loudness contours and phons |
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29 | (1) |
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What we can deduce from equal loudness contours |
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30 | (1) |
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31 | (2) |
| Section 4. Dynamic Range |
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33 | (2) |
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33 | (1) |
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The dynamic range of a typical rock concert |
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33 | (1) |
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The electrical dynamic range of the sound system |
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33 | (1) |
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The acoustical dynamic range of the system |
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34 | (1) |
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35 | (2) |
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35 | (1) |
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Why headroom is important |
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36 | (1) |
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Manipulating dynamic range in a practical sound system |
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37 | (6) |
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Why not build a sound system with excess dynamic range? |
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37 | (1) |
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What happens when the sound system is inadequate? |
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37 | (2) |
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How to fit wide program dynamics into a sound system with limited dynamic range |
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39 | (3) |
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How much headroom is adequate? |
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42 | (1) |
| Section 5. Sound Outdoors |
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43 | (2) |
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Inverse square law calculations |
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44 | (1) |
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Effects of environmental factors |
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45 | (2) |
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45 | (1) |
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46 | (1) |
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46 | (1) |
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47 | (6) |
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Maximum gain (available gain before feedback) |
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47 | (2) |
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Using directional microphones and loudspeakers |
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49 | (4) |
| Section 6. Sound Indoors |
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53 | (2) |
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The absorption coefficient |
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54 | (1) |
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55 | (2) |
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56 | (1) |
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57 | (1) |
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58 | (3) |
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Implications for sound reinforcement |
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60 | (1) |
| Section 7. Block Diagrams |
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61 | (2) |
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63 | (3) |
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66 | (1) |
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Analysis of simple block diagrams |
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67 | (3) |
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70 | (1) |
| Section 8. How to Read & Interpret Specifications |
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71 | (1) |
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Why specs are not always what they seem |
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71 | (1) |
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Examples of specs that should be doubted |
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71 | (1) |
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72 | (1) |
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72 | (3) |
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Distinguishing frequency response, frequency range, and power bandwidth |
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72 | (2) |
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Graphic versus printed specs |
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74 | (1) |
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What is a good frequency response spec? |
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74 | (1) |
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75 | (6) |
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75 | (1) |
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76 | (1) |
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76 | (1) |
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77 | (1) |
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EIN: a measure of mic preamplifier noise |
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78 | (1) |
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78 | (2) |
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80 | (1) |
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81 | (4) |
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What is harmonic distortion? |
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81 | (1) |
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Measuring harmonic distortion |
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82 | (2) |
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Factors affecting harmonic distortion specifications |
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84 | (1) |
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Intermodulation distortion |
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85 | (2) |
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85 | (1) |
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86 | (1) |
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How much distortion is tolerable? |
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86 | (1) |
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Transient intermodulation distortion |
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86 | (1) |
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Input and output impedances |
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87 | (5) |
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Confusion about input and output impedances |
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88 | (2) |
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88 | (1) |
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89 | (1) |
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The implications of impedance mismatches |
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90 | (1) |
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91 | (1) |
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Standard operating levels |
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92 | (4) |
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General classification of levels |
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92 | (1) |
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Expressing the wide power range of a sound system |
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93 | (1) |
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How impedance relates to level specifications |
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94 | (1) |
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94 | (1) |
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94 | (1) |
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How the load affects output voltage |
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95 | (1) |
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What happens when hi-fi and pro equipment mix |
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95 | (1) |
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Hi-fi output to pro equipment input |
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95 | (1) |
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Pro equipment output to hi-fi input |
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96 | (1) |
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96 | (3) |
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97 | (1) |
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97 | (1) |
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Specification of crosstalk |
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97 | (2) |
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Filter slope rates and turnover frequencies |
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99 | (1) |
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100 | (3) |
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101 | (2) |
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What not to expect with square waves |
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103 | (1) |
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103 | (2) |
| Section 9. Why Ears Don't Always Correlate With Specs |
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105 | (2) |
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105 | (1) |
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Average ears vs ``golden ears'' |
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106 | (1) |
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Test equipment measurements vs listening tests |
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107 | (4) |
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Test signals versus program material |
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107 | (2) |
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Location and number of test microphones |
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109 | (1) |
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110 | (1) |
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111 | (1) |
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Masking effects and equipment interaction |
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112 | (1) |
| Section 10. Microphones |
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113 | (3) |
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113 | (1) |
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113 | (1) |
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114 | (1) |
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114 | (1) |
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115 | (1) |
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116 | (1) |
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116 | (5) |
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116 | (1) |
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117 | (1) |
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117 | (1) |
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118 | (1) |
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118 | (1) |
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119 | (1) |
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119 | (1) |
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120 | (1) |
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Noise cancelling microphones |
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120 | (1) |
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Acoustical and electrical characteristics |
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121 | (8) |
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121 | (3) |
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121 | (1) |
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121 | (2) |
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Bidirectional or figure-8 |
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123 | (1) |
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123 | (1) |
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124 | (1) |
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125 | (1) |
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125 | (1) |
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Output level or sensitivity |
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126 | (1) |
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126 | (1) |
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127 | (1) |
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Balanced and unbalanced connections |
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127 | (2) |
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129 | (3) |
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Windscreens and pop filters |
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129 | (1) |
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129 | (1) |
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130 | (1) |
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Effect of the number of open microphones |
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130 | (1) |
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Gain and microphone placement |
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131 | (1) |
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131 | (1) |
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Wireless intercom systems |
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132 | (7) |
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What is a wireless intercom? |
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132 | (1) |
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Who uses wireless intercoms? |
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132 | (1) |
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What is the background of wireless intercoms? |
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133 | (1) |
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Types of wireless intercoms |
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133 | (2) |
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135 | (1) |
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Improved range and noise reduction |
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136 | (1) |
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Evaluating and selecting a system |
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136 | (1) |
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137 | (1) |
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Glossary of wireless intercom terms |
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138 | (1) |
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Wireless microphone systems |
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139 | (10) |
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139 | (1) |
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139 | (1) |
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What is the background of wireless mics? |
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139 | (1) |
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140 | (1) |
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141 | (1) |
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142 | (3) |
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Compatibility of wireless mic systems |
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145 | (1) |
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146 | (1) |
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Evaluating wireless microphone systems |
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146 | (1) |
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147 | (1) |
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Glossary of wireless microphone terms |
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148 | (1) |
| Section 11. Preamplifiers, Small Mixers, & Mixing Consoles |
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149 | (3) |
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152 | (2) |
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What are they, and what do they do? |
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152 | (1) |
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153 | (1) |
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153 | (1) |
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154 | (1) |
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155 | (7) |
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155 | (1) |
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How mixes differ: pre & post fader considerations |
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155 | (2) |
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Panning, summing and master faders |
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157 | (5) |
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Understanding console specifications |
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162 | (5) |
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How many inputs, mixes and outputs? |
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162 | (1) |
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162 | (2) |
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164 | (1) |
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165 | (1) |
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166 | (1) |
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Transformer isolated versus electronically balanced inputs & outputs |
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167 | (5) |
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Transformers versus differetial amps: price concerns |
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168 | (1) |
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Discrete versus IC differential amps |
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168 | (1) |
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The case for the transformer |
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169 | (1) |
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Transformers and AC safety |
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170 | (1) |
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170 | (2) |
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Gain staging and gain structure |
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172 | (3) |
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Why does gain have to be manipulated? a review of sound levels fed to the console |
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172 | (1) |
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Gain control at the microphone input |
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173 | (1) |
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Input attenuation or padding |
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173 | (1) |
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Eliminating other causes of signal-level (& gain) related distortion |
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174 | (1) |
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174 | (1) |
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174 | (1) |
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Interface with sub-mixers |
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175 | (3) |
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Stage monitor mixing consoles |
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178 | (4) |
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What is a stage monitor system? |
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178 | (1) |
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Why a monitor console is preferable to a mix from the main house console |
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179 | (1) |
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The importance of a high quality monitor mix |
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180 | (1) |
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Other benefits of a separate monitor console |
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180 | (1) |
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Polarity (phase) reversal as a tool to fight feedback |
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181 | (1) |
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Eliminating SCR dimmer noise |
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182 | (1) |
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182 | (4) |
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183 | (1) |
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Additional isolation for high-noise environments |
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184 | (1) |
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Splitting a mic without a transformer |
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185 | (1) |
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Reducing feedback in the stage monitor system |
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186 | (3) |
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186 | (1) |
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Polarity reversal (or ``phase'' reversal) |
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186 | (1) |
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Ringing out a monitor system |
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187 | (2) |
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Aiming monitor loudspeakers |
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189 | (1) |
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189 | (4) |
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Additional monitor console placement factors |
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189 | (1) |
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Main house mixing console placement |
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190 | (3) |
| Section 12. Power Amplifiers |
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193 | (1) |
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Ohm's law & related equations |
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193 | (4) |
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Voltage, resistance and current |
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193 | (1) |
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194 | (1) |
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195 | (1) |
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Electrical power and amplifier gain |
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196 | (1) |
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Power ratings of amplifiers |
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197 | (5) |
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198 | (1) |
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198 | (1) |
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Slew rate and output power |
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199 | (1) |
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200 | (1) |
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201 | (1) |
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The relationship between amplifier power and SPL |
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202 | (2) |
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Matching power amplifiers to loudspeakers |
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204 | (5) |
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Interpreting loudspeaker power ratings |
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204 | (1) |
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205 | (3) |
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Constant-voltage distribution systems |
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208 | (1) |
| Section 13. Loudspeakers |
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209 | (1) |
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Common methods of acoustic transduction |
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210 | (2) |
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Electromagnetic transduction |
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210 | (1) |
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Piezoelectric transduction |
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211 | (1) |
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212 | (2) |
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Directional characteristics of cone drivers |
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213 | (1) |
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214 | (4) |
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215 | (1) |
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216 | (2) |
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218 | (1) |
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219 | (3) |
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222 | (6) |
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222 | (1) |
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Passive, high level crossovers |
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223 | (2) |
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Active, low level crossovers |
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225 | (3) |
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225 | (2) |
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227 | (1) |
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227 | (1) |
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227 | (1) |
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Biamp or triamp versus conventional system |
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227 | (1) |
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228 | (2) |
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Effect of boundary conditions |
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229 | (1) |
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Loudspeaker specifications |
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230 | (6) |
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230 | (1) |
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231 | (1) |
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232 | (1) |
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233 | (1) |
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Directional characteristics |
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234 | (2) |
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236 | (2) |
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236 | (1) |
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Intermodulation distortion |
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236 | (1) |
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237 | (1) |
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238 | (6) |
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238 | (1) |
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239 | (2) |
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Failures due to other components in the signal chain |
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241 | (3) |
| Section 14. Signal Processing Equipment |
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244 | (15) |
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244 | (1) |
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244 | (2) |
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Multi-band conventional equalizers |
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246 | (2) |
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248 | (1) |
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248 | (3) |
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251 | (3) |
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254 | (1) |
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Tuning a sound system with graphic (or paragraphic) equalization |
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254 | (2) |
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High pass and low pass filters |
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256 | (3) |
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259 | (11) |
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261 | (1) |
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262 | (1) |
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262 | (2) |
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264 | (1) |
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264 | (2) |
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266 | (1) |
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267 | (2) |
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269 | (1) |
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270 | (4) |
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270 | (1) |
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How compressor/limiters work |
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271 | (1) |
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272 | (2) |
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274 | (3) |
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274 | (1) |
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275 | (1) |
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276 | (1) |
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277 | (2) |
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277 | (1) |
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278 | (1) |
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278 | (1) |
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279 | (2) |
| Section 15. Cabling |
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The importance of good cables |
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281 | (1) |
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Types of cables, their construction and use |
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282 | (9) |
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Electrostatic and electromagnetic shielding |
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282 | (1) |
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283 | (1) |
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Single and dual conductor shielded cables |
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284 | (3) |
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287 | (1) |
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Unshielded cables and speaker cables |
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288 | (1) |
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Multicore audio cables (``snakes'') |
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289 | (2) |
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291 | (12) |
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291 | (1) |
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291 | (6) |
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297 | (2) |
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299 | (4) |
| Section 16. Sound System Test Equipment |
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303 | (2) |
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305 | (2) |
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307 | (2) |
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309 | (1) |
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The sound pressure level meter |
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310 | (1) |
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311 | (1) |
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312 | (1) |
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312 | (1) |
| Section 17. The Electronics |
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313 | (2) |
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Sound reproduction systems |
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313 | (1) |
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Sound reinforcement systems |
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314 | (1) |
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Developing a logical system architecture |
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315 | (10) |
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316 | (1) |
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317 | (8) |
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325 | (2) |
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Signal levels and impedance |
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325 | (1) |
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Unbalanced and balanced connections |
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326 | (1) |
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327 | (6) |
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Why is proper grounding important? |
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328 | (1) |
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329 | (1) |
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Basic grounding techniques |
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330 | (3) |
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Using audio signal transformers |
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333 | (4) |
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Properties and functions of signal transformers |
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333 | (2) |
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Some practical applications |
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335 | (2) |
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337 | (5) |
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Verify the correct mains voltage |
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337 | (1) |
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Ensure there is a good earth ground |
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338 | (1) |
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How to obtain a safety ground when using a two-wire outlet |
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339 | (1) |
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Imporperly wired AC outlets: lifted grounds |
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339 | (1) |
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Improperly wired AC outlets: lifted neutral |
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340 | (1) |
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341 | (1) |
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341 | (1) |
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341 | (1) |
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Configuring equipment racks |
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342 | (1) |
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343 | (4) |
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343 | (1) |
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343 | (4) |
| Section 18. the loudspeakers |
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Analyzing the application |
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347 | (1) |
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347 | (1) |
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348 | (1) |
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348 | (3) |
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349 | (1) |
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350 | (1) |
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351 | (1) |
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351 | (4) |
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Directionality and coverage |
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351 | (2) |
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353 | (1) |
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353 | (1) |
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Controlling feedback indoors |
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354 | (1) |
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Loudspeaker placement indoors |
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354 | (1) |
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355 | (3) |
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355 | (1) |
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355 | (2) |
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357 | (1) |
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358 | (1) |
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Setting electronic crossovers |
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358 | (6) |
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Choice of crossover frequency and slope |
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358 | (2) |
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Setting up the loudspeaker system |
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360 | (1) |
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Testing and optimizing the system |
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361 | (2) |
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High frequency driver protection networks |
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363 | (1) |
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364 | (4) |
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368 | (1) |
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368 | (3) |
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368 | (1) |
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Multiple loudspeaker systems |
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369 | (1) |
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370 | (1) |
| Section 19. MIDI |
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371 | (4) |
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372 | (1) |
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373 | (1) |
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374 | (1) |
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374 | (1) |
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Control of musical instruments |
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375 | (7) |
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377 | (1) |
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378 | (1) |
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Patch editor/librarian functions |
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379 | (1) |
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MIDI implementation charts |
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380 | (2) |
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382 | (5) |
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382 | (1) |
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383 | (2) |
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Hardware vs computer-based sequencers |
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385 | (1) |
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Typical sequencer features |
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385 | (2) |
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386 | (1) |
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386 | (1) |
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386 | (1) |
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387 | (2) |
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387 | (1) |
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387 | (1) |
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388 | (1) |
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388 | (1) |
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388 | (1) |
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389 | (2) |
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389 | (1) |
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390 | (1) |
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390 | (1) |
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391 | (1) |
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391 | (4) |
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391 | (1) |
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392 | (1) |
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392 | (1) |
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393 | (2) |
| Section 20. Synchronization |
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395 | (3) |
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395 | (1) |
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396 | (1) |
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397 | (1) |
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398 | (8) |
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398 | (2) |
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Frame rates and line references |
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400 | (1) |
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Longitudinal, vertical interval and visible time code |
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401 | (1) |
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402 | (2) |
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402 | (1) |
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402 | (1) |
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403 | (1) |
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403 | (1) |
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Advanced transport controls |
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403 | (1) |
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403 | (1) |
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404 | (1) |
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404 | (1) |
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405 | (1) |
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405 | (1) |
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406 | (6) |
| Appendix A. Logarithms |
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A.1 Raising Numbers to a Power: The Key to Logs |
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409 | (1) |
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A.2 Simple Logs (and Antilogs) to the Base 10 |
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409 | (1) |
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A.3 Less Obvious Logs to The Base 10 |
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410 | (1) |
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A.4 Mathematical Properties of Logs |
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411 | (1) |
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A.5 One More Look At Logs and Decibels |
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|
412 | (1) |
| Index |
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Other versions by this Author