Sound Characteristics 1 of 3
Before we can even star to manipulate sounds, we first need to understand what it is. Sound is energy that travels trough the air, or other substances such as water or even solids, in the form of waves. These waves of energy are called sound-pressure waves and are created by something pushing the air together. The best way to to imagine this is to picture an inch worm crawling. As it moves along, its back legs move forward to its fronts legs and its back is pushed up into the air. Then it moves its front legs forward till its flat and then does it again to continue to crawl along. Now picture air doing the same thing but its invisible and does it much faster.
Because Sound is a wave, it has the same characteristics as other waves. There are 7 parts of a wave and we need to know how they effect the sound. If we have this knowledge, we will be able to become a better audio engineer. The 7 Waveform characteristics are:
- Amplitude
- Wavelength
- Velocity
- Frequency
- Phase
- Harmonic
- Envelope
Amplitude
Amplitude is the hight of a wave. If a surfer is taking about catching 10 footers on his last trip to Hawaii, he is talking about the amplitude of the ocean waves. Loud sounds are going to have higher waves, while quiet and soft sounds are going to have smaller waves.
Wavelength
Wavelength is what determines the pitch of the sound is. Low sounds are going to have longer waves, up to several feet long. At the same time, higher sounds are going to have shorter waves which are less than and inch long.
Velocity
The speed that sounds travels through the air is about 1130 feet per second at a temperature of 68 degrees Fahrenheit (344 m/sec at 20 C) . This will change at 1.1 feet per second for every degree in temp temperature change.
This will be all I cover today. Later this week I will cover the rest of the characteristics of sounds, starting with Frequency, and I’ll also get into some other important terms you will need to know as a sound engineer.
