1. EFC Media Center Training

2. Introduction What is Sound ? Properties of Sound Speed 340m/s
Frequency / Pitch
Loudness / SPL

4. Introduction Range (dB Sound Pressure Level) 0 - 30 Very Quiet
This is the threshold of human hearing, up to the sound of a quiet whisper.
Quiet
This is an average quiet house, with maybe the sound of a fridge running or someone moving around.
Normal
Regular daily sounds like people talking.

5. Introduction
Loud
This is the point where a sound becomes annoying or distracting. Vacuums or a noisy car on a busy street are at these levels.
Very Loud
Most people will try to avoid being in areas this loud. Prolonged exposure can cause permanent ear damage. Temporary effects, like "stereo hiss", may happen.
111 + Painful!!!
Even limited exposure to levels this high will cause permanent hearing loss.

6. Introduction How do we perceive sound 20 ~ 20KHz range
Perceived loudness at different frequency
Perceived spectral response at different average loudness level

8. Introduction Purpose of Audio System in Church
Amplify voices so that it will be noise free, intelligent, with sufficient volume even for our elderly.
Purpose of Sound Engineer
To operate and maintain audio equipments so that our congregation is free to worship without distractions.