Understanding the science behind how you perceive sounds, how sounds travel, and how sounds are produced and measured—this knowledge is essential for anyone aspiring to become an audio engineer. The best live sound engineers don’t simply have a basic understanding of sound and hearing: it is more second nature. In this first chapter, we’ll provide you with the knowledge, and it is up to you to turn that knowledge into second nature.

Obviously, as a live sound engineer, you will always be working with microphones. In this chapter, you will learn the basics concerning the history, anatomy, and general application of most relevant microphone types and patterns. Be warned, this chapter might be the one that first triggers a gear addiction you never knew you had.

You may think you already know the answer to this question, but if your answer is only one sentence long, think again. In this chapter, you will learn about every peripheral that could constitute a live sound system, and the science behind each of them.

Beyond manufacturing quality and materials, what sets two different brands of speakers or microphones apart from each other? Answer: their frequency response. You will learn multiple definitions for this frequently used term, and examine how it relates to various types of audio equipment.

Did you think that by being a live sound engineer, you could completely elude ever having to use math? If so, you were wrong. The decibel unit measures sound level the same way miles or meters measure distance. But there are also variations of this audio measurement unit when related to sound pressure level, volts, watts, ohms and so on. In this chapter, you will begin to understand why "engineer” is in the job title.

Dynamic range is the difference in decibels between the loudest and quietest portion of a live performance. Headroom is the difference between the loudest part of a performance and the loudness threshold that your sound system can handle. In this chapter, you will learn the importance of controlling the dynamic range and compensating for possible peaks with headroom.

The absence of walls and a ceiling changes the behavior of sound and affects sound systems differently than indoor concerts. Some of the highest paying gigs a live sound engineer will work are outdoor festivals and concerts. That being said, you’ll definitely want to pay close attention to this chapter, as you will learn to control sound in less predictable environments.

This section discusses the behavior of sound indoors and is a continuation of the previous chapter. Inside the walls of an indoor space, reverberation, distance, and absorption will be your main obstacles. You will learn to overcome them, as the majority of your work will most likely be in indoor clubs and concert halls.

Though it’s the friend of the electric guitar player, and the underground music scene in general, harmonic distortion is one of the live sound engineer’s worst enemies. But, as the saying goes, keep your friends close, and your enemies closer. In this section, you learn to do just that: you will learn scientifically how to measure and control harmonic distortion in live scenarios.

What does impedance mean for the operator of a sound system? If you have an array of speakers, which and how many amplifiers would you need? In this chapter, you will learn how to not destroy the sound system by gaining a mathematic understanding of input and output Impedance.

In this chapter, you will delve deeper into the word of microphones. You will gain an in-depth knowledge of every type of microphone, their pickup patterns, and how all these previous chapters and the principles they teach apply to choosing the right microphone for the right application.