One of the first questions is “should I buy a 5.1 or 7.1 channel receiver?” Look at the drawing below supplied by Dolby Labs. If you remove the #4 speakers, you have a 5.1 setup. This has been the standard for years and if you look on the back of your DVD package, you will see under the language heading, “English 5.1 Dolby Digital.” 5.1 is the ideal format for a small to medium size room.
A 5.1 channel system consists of a receiver, usually one that plays DVDs. It has a center channel, which is important for dialog and musical vocals; two front speakers, which are used for the soundtrack and stereo music; two rear or surround speakers for motion and ambient sounds; and a subwoofer, which responds to the bass, explosions and sounds lower than the center speaker can handle.
When shopping for a sound system, listen to the center channel at a distance where you would normally sit and listen to the voices. If they are not clear and easily heard, look for a better system. If you shop at a retail store, this might not be practical. Shop where you can get the full impact of the sound system, which you are considering. Remember, you will be living with this system for years to come.
A 7.1 system is more expensive and might be over kill for your DIY project, as it adds two additional speakers located in the middle of the side walls (See above diagram, speakers #4). A 7.1 environment would add more depth to the surround sound experience.
Today, most Blu-ray soundtracks are 5.1, but more are starting to include 7.1 channel information. Only you can decide which of the two systems will best suit your project.
Most receivers have all of the standard audio connectors, such as RCA, S-Video and component video. The new standard is HDMI or high definition multimedia interface. This single cable carries high def video and multi-channel audio. Make sure the system that catches your eye has HDMI. Before you walk out of the store, check to see if this cable is included or optional. You don’t want to get home and find you have to make a return trip.
The Sony BDV580 is a good example of the 5.1 channel Home Theater System, which is priced middle of the road, but has features that are found on higher end products. It has a 1080p Blu-ray player with a 1000 Watt Amp and comes with 2 HDMI connections.
At the upper end of Home Theater systems is the Bose Lifestyle V-Class system, which is easy to install using the Bose onscreen easy to follow messages. It even verifies that the proper connections are made. With a software update, this system can be upgraded to be used with 3-D.
The Bose ADAPTiQ audio calibration system analyzes your room dimensions and adjusts the sound to the acoustics of the room. The Bose system is strictly a sound system. You will need a DVD player.
If you want a different approach to speakers rather than buy a system where the components have been selected for you, you might look at Paradigm speakers. No matter which speakers you need from a center speaker to a subwoofer, you can select the quality speaker that fits your lifestyle and match the individual speakers.
Once you decide on the number of channels you would like to have, you have to consider the placement. The important part of speaker placement is in the listening. The final placement of your speakers will be the location that gives you your best sound.
Because you might want to add drapes to spice up the dÃ©cor, you should consider placing the speakers on speaker stands and not hang them on the walls. Speakers vibrate and the walls absorb this vibration, taking away from the quality of the sound. Start with the center channel, which should be placed directly below the screen in the center. As stated previously, this is the most important speaker in the home theater system, as it will handle 80% of the sound.
The ideal locations for the right and left front speakers are about two feet from the side of the screen and level with the viewers’ ears. If there is enough room, keep these speakers away from the front and side walls to minimize sound reflection from these surfaces. Experiment with the positioning of the front speakers until the prime viewers are satisfied with what they hear. If you are good with math and can work out angles, you might want to start with these speakers angled 22 â€“ 30 degrees from center to the middle of the listening area as a starting point. Make sure that the speakers are placed at an equal distance from the center, as even a small variation will make a difference. If you are not a math wiz, use your ears. They will tell you when the speakers are placed correctly.
Every room has resonances where the room’s dimensions will reinforce or diminish the bass wavelengths. Therefore, set the subwoofer asymmetrically with respect to the room’s dimensions. What does this mean? Place the subwoofer at a position that does not have a mathematical relationship, such as placing the subwoofer three or five feet in from the corner of a 12′ wall. 12 â€“ 5 = 7. There is no mathematical relationship here, but if you place the subwoofer six feet out, the relationship will be 2:1, which would reinforce or cancel the frequencies.
The rear speakers are the surround speakers. They should be placed near or at the rear of the room, but away from the walls. The angle for the surround speakers should be 90 â€“ 110 degrees to the center. Do not place them so far behind the last row of seats that the listeners are out of the surround range. Again, experiment.
Don’t forget the raceways so that the speaker wires are concealed and you don’t have your guests tripping and damaging your speakers.
Stay Tuned for Part 4 – Everything Else
This article contains statements of personal opinion and comments made in good faith in the interest of the public. You should confirm all statements with the manufacturer to verify the correctness of the statements.