Getting Started with Audio
How then shall they call on him in whom they have not believed? and how shall they believe in him of whom they have not heard? and how shall they hear without a preacher? - Romans 10:14
Audio is a vital part of ministry in the 21st century. If sound is not loud enough, or is muffled or unclear, people might have a hard time understanding what is being said. To provide the best quality audio, there are a range of things we need to understand.
In the guide, we will start from the very beginning. We will learn what sound is, how sound systems work, and how to hear all the nuances of sound, whether in a big auditorium, or on a podcast on your phone. This is valuable regardless of your experience, but if you have not worked much with sound before, work through this guide carefully before moving on to selecting the equipment or setting up the sound systems for your church.
Understanding Sound
What is sound exactly? If you've never thought seriously about how sound works, watch this short video: (1 minute, 21 seconds)
Okay, so sound is made up of waves. There are various sources of sound though. In order for a sound to be made, something needs to disrupt the air. Sound is always the result of two things colliding. Some things, like strings, can continue to resonate after they have been plucked or struck, but the original sound comes from a kind of impact.
It might be worth a tangent at this point into the wonderful world of "Foley", where artist/actor/engineers make the sounds that we hear in the movies. Watch this great introduction to Foley on YouTube. (6 minutes)
frequencies and harmonics
If you want to dig deeper into how sound works, including frequencies and harmonics, here is a series of thorough YouTube videos on the subject. This series focuses a little more toward the music side of sound, but all of this knowledge will be helpful for you as you move forward in dealing with sound.
- How Music Works
- What is Sound?
- What is the difference between noise and note?
- Frequency, Wave Shape and Pitch
- Amplitude, Phrase and Envelope
- Beats and Just Noticeable Difference
- Why is A 440 Hz?
- Do Drums Make a Noise or a Note?
- The Overtone Series and Timbre
- The Overtone Series and Dissonance
- The Missing Fundamental
- Why are low notes muddy and high notes weak?
- Inharmonicity and Octave Stretching
- Infrasound & Ghosts
- Avoiding the 7th Harmonic
Audio System Topology
Let's begin with an overview of how sound systems are generally set up.
Microphones
There are a range of different kinds of microphones, each with it's own purpose.
Cables and Connections
1/4 inch, XLR, cable types, phantom power
The "Mixer"
Big picture
Channels Only
Routing
Enhancing the sound (eq, effects, etc.)
Output
The "Amp"
Speakers
Ok, so where do you place the speakers? There is actually some science involved in how sound works. For an introduction, see this video about how sound works in a room.
To see how speakers work, here is a video the does a great job of demonstrating the inner workings of speakers.