Home theater systems normally come in three digital audio applications; Dolby Digital 2.0, 5.1 and 7.1, with the decimal number (.1) being the sub woofer, and the real number being the number of speakers that the receiver supports. So, a Dolby Digital 5.1 home theater system would have a sub woofer, two front and two rear surround sound speakers, and a center channel speaker (5 speakers and a sub woofer).
The center channel speaker is responsible for the vocals, or the actor's voices, and is the most important speaker with regards to quality and placement position in the room. The main factors in figuring out how to set up a Dolby Digital 5.1 home theater system would start with the placement of the television set, which should be positioned so that no windows or entrance doors are in the reflection of the screen. Too much back lighting will ruin the picture, and make the darker scenes very hard to make out.
Once the placement of the television has been set, the rest is rather easy. Place the home theater system receiver beside the television set either on a wall unit or an entertainment unit. The front of the receiver should be fully visible, as the remote control is directional and needs to have a direct line of sight to the receiver. Place any other components with the receiver, either above or below, so that the connections can easily be made. Before attaching components and speakers to the receiver, make sure that you purchase quality connection cables and speaker wires, since any audio system is only as good as its' weakest link. It would be a shame to have a good system, and use cheap cables and wires to connect them, as the information carried through these cables and wires is what is delivered to your receiver and speakers. If the receiver has fiber optic audio-in connections, use this feature to connect the audio from any PVR, Blu-ray or DVD player. Use the S-Video for any and all video connections, as this is the best option for clean, clear picture transfer to the television.
Before hooking up the individual speakers, connect all of the wires to their respective connections on the rear of the receiver. Run the wires to about where each speaker will be placed, and add about two to three feet of extra wire, in case of minor adjustments later. The front channel speaker should be positioned as close as possible to the television, so that the actor's voices appear to come from the screen. The sub woofer placement should be not in a corner or under any furniture, but other than that the placement can be anywhere in the room so that the sub woofer faces the listener. The front surround sound speakers should be placed at least three feet from both the receiver and center channel speaker. If your room is larger, make the separations greater, as long as you can match the distance between the front speakers and the receiver with the distance between the front speakers and the rear speakers. Place the rear surround sound speakers equidistantly from the front speakers and the center channel speaker.
The most important thing to consider when placing the surround speakers is to make them all focus on the sweet spot of the listener. The sweet spot is defined as the position in which the viewer most frequently sits to watch the television. With the speakers positioned equidistantly from each other and the sweet spot, make sure that they are all positioned to face the sweet spot. Once all speakers are positioned properly, use the owners manual of the home theater receiver to calibrate the speakers, to make sure that you get the same amount of volume from each speaker. Once this has all been done, it is time to watch a movie!