In this instructable I will cover phasing of speakers. This is designed to be just a introduction to phasing, some phasing techniques are very advanced, however, I will show you what I think is the easiest way to think about phasing.
Step 1: What is phasing?
Many people might ask: "What is phasing?". That can be very difficult to explain, but I will do my best. When you produce artificial sound from multiple sources, you always run the risk of being out of phase. What I mean by out of phase is this: one source is "contradicting" what the other source is doing. When a speaker produces sound, it is vibrating back and forth. When you phase a speaker, the idea is to have both speakers moving in the same direction.
Step 2: When do you need to phase?
Let's determine if you even need to phase your speakers. There are a three questions you need to ask yourself.
1. What were these speakers meant to do? (Pro Audio, Stereo system, Surround Sound, etc.)
2. What was the amplifier meant to do? (Pro Audio, Stereo system, Surround Sound, Powered Speakers, etc.)
3. What orientation was the system designed to be used in? (Facing each other, same direction, surround, etc.)
If you are using the system in the way it was designed, then you do not need to phase the speakers. But if you have a system that was designed to be used with the speakers facing each other and they are now facing the same direction, or you have a system that was designed to be used with the speakers facing the same direction and they are now facing each other, you need to phase them.