Tyco 579-769 specifications Table of Contents

Table of Contents

Chapter 1 Speech Intelligibility Overview	1-1
Introduction	1-1
Chapters of this Publication	1-1
In this Chapter	1-1
Importance of Audible and Intelligible Emergency Communications	1-2
Speech Intelligibility Importance	1-2
Designing for Intelligibility	1-2

Chapter 2 Background Information	2-1
Introduction	2-1
In this Chapter	2-1
Basic Audio Math	2-2
Ohm’s Law and the Decibel	2-2
Adding Decibels	2-3
Sound and Hearing	2-4
The Relationship Between Sound and Hearing	2-4
The Nature of Speech	2-5
Introduction	2-5
Consonants and Vowels	2-5
Room Acoustics	2-6
Introduction	2-6
Reverberation	2-6
Estimating Reverberation Times	2-7
Countering the Effects of Reverberation	2-7
Speaker Basics	2-9
Inverse Square Law	2-9
Sensitivity	2-10
Speaker Dispersion Angle and “Q”	2-10
Speaker Coverage	2-12
Determining Critical Polar Angle	2-13
Determining Critical Polar Angle	2-14
Power Rating	2-15
Speaker Layouts	2-15
Distributed Wall Mounted Systems	2-16
Introduction	2-16
Advantages	2-16
Disadvantages	2-16
Design of a Distributed Wall Mount System	2-17

Chapter 3 Speech Intelligibility	3-1
Introduction	3-1
In this Chapter	3-1

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