How To Buy a Home Theatre System

The main components of a home theatre are a display unit (Television or projector) , an AV receiver/ amplifier, a 2.1, 5.1, 6.1 or 7.1 speaker system and a DVD player. It is important to find a convenient room and analyze the room to determine its requirements before you purchase any component.

The size of the room determines the dimension of the units. If the size of the room is large, you can use a large sized TV. The main factors of a room that influence the home theatre experience are:

• (i) The ambient light of the room. A dark room has the better quality of viewing
• (ii) The area of the room. Placing a small TV in a large room may not give the rich cinema experience.
• (iii) The type of walls. The quality of sound depends on the type of the walls.
• (iv) Don't place the TV opposite to any source of light especially windows or doors.
• (v) The type of floor. The floor may reflect the sound and deteriorate its quality.

Study the room and locate the position of each unit. If you are not sure where everything should go, consult a qualified technician.

Read the following sections to understand each unit. If you are not comfortable in understanding each unit and buying them separately, the easiest way is to buy a Home theatre in a box system. It contains the whole home theatre as a single package.

1. Display unit- the TV or Projector: You need a display system to see the picture. You can use a TV or a projector for this purpose. Understand the specifications of the display unit before buying it. The important specifications are explained below.

   The resolution of the video is important. The resolution is the number of dots or pixels [pixel is the abbreviation of picture element] that make a complete picture. The higher the resolution the better the clarity of the picture. DVDs store video in 720x 480 format in NTSC format and 720x578 for PAL [PAL, NTSC, SECAM are color video encoding standards used in different countries or regions]. 720x480 means that an image is formed with 720x480 dots. HD means High Definition. HD contains more dots, which makes the picture quality better. High Definition TV can display up to 1920x1280 pixels.

   Resolutions are marked as 480p, 1080i etc. The ‘p’ suffix indicates progressive scan and ‘i’, the interlaced scan. The dots are usually arranged as rows and columns. In a progressive scan, all the lines in a picture are displayed in a single go. But interlaced scan, the odd lines and even lines of a picture are displayed alternately. The progressive scan is better than interlaced scan. So ‘p’ is better than ‘i’.

   The aspect ratio is a common specification of the display devices. It is the ratio of the width of the display screen to its height. Typical values are 4:3 and 16:9. If the picture appears stretched or clipped while you are watching the movie, look at the DVD specification (found on the DVD cover) and adjust the aspect ratio of the display unit to match it. There are other types of aspect ratios, like widescreen and full zoom.

   • Television: The most common display device is the TV with CRT [Cathode Ray Tube]. The picture quality, levels of saturation, color tones, brightness and clarity of CRT type are good. Nowadays, flat panels are becoming popular. Flat panels basically consist of two types- LCD [Liquid Crystal Display] and Plasma. The cost of LCD and Plasma TVs is falling rapidly day by day.

     The size of the TV screen is measured across it diagonally. The minimum recommended size of a TV is 32 inches. However, you can choose the TV size depending on the space you're placing it in.

     High Definition Television (HDTV) gives much better performance than the traditional TV. The HD compatible TVs are compatible with the latest HD devices as well as older VCRs/DVD players.

   • The Projector: You can use a projector as the display device. Projectors display the image in a large area, giving a cinema hall experience. The common types are DLP [Digital Light Processing] and LCD [Liquid Crystal Display]. I personally recommend a DLP projector for home theatre systems. Use a very dim light for a better viewing experience. One main draw back of a projector is that the lamp in it has a limited lifespan. The typical lamp life is 3000 hours. You need to replace the lamp after its life expires or it blows out. The cost of the lamp is comparatively high.

     If you are using a projector, spend some money to buy a good display screen.

2. AV Receiver: An AV receiver is an amplifier that amplifies the sound signals coming from the DVD player. The AV receiver has enough inputs and outputs to connect many devices. It can switch and control various audio and video sources [DVD player/ VCR/ CD player/ Game consoles]. It can also route various video inputs coming from different sources to the TV. It processes the input sound signals and sends them to the amplifier and subwoofers.

   It also decodes the digital audio signal and converts to the analog signal that is suitable for speakers. The sound output of the AV receiver goes to the speakers and video to the TV. You can connect the video output of the DVD player directly to the display unit if you don’t have multiple video players and game consoles.

3. Sound system: The 2.1, 5.1, 6.1 and 7. 1 speaker systems are popular. A 5.1 speaker system means that there are 5 speakers with a subwoofer. The number before the dot indicates the number of speakers and the 1 after the dot indicates the number of subwoofers in it. Among the above systems, 5.1 is the most popular today.The buzz word related to home theatre is ‘surround sound’. There are 2 major companies making surround sound format- Dolby and DTS [Digital Theatre system]. The surround sound format is encoded in the movie available in the Disc. This format is decoded by the AV receiver and sent to the corresponding speakers.

   The AV receiver has built-in multi channel amplifiers [2.1, 5.1, 6.1, 7.1 channels] that send the sound signal to the corresponding speaker. High-end systems have separate units for each function like preamplifiers, tuners and a separate amplifier for each channel. These units provide more flexibility.

   Select the number of speakers depending on the size and type of the room. Before you purchase a speaker system, ensure its quality. Play some high quality DVDs/CDs in the audio system with speakers before you make the final purchase decision. It is always better to have all the components of the audio system made by same brand. A Sub woofer is a special speaker that plays only extremely low frequency audio signals -- the bass.

4. Arrangement of speakers: Now let us see how the speakers are arranged in a room. I strongly recommend a minimum of a 5.1 system. First, place the Television in its proper location. Then, keep the center speaker below or above the TV. This speaker delivers all the dialogues. Place the front speaker pair on either side of the TV. These front speakers give the background music and the ambient sound effects of the movie. The other speaker pair are the rear speakers and they are kept behind the audience (i.e. you!). These speakers deliver the motion effects, dialogue panning and ambient sound effects.

   Place the sub woofer between the front speakers. You can adjust the phase control of the subwoofer to get the best sound effect in the room.

5. The Video player: You need a player that can play a movie or music. The device can be DVD, VCD or DivX CD. DVD is the most common format available. Most of the DVD players can play CD video/audio, MP3 audio etc. Blu-ray and HD-DVD are new-entrants and have better quality content. The cost of the Blu-ray and HD-DVD are high, but can be worth the price.

   Usually the movie or music is available in CD (Compact Disc) or DVD (Digital Versatile Disc). The DVD player can play both CDs and DVDs whereas the CD player can play only CDs and not DVDs.

   If a movie is available in both CD and DVD, buy the DVD for better quality picture and sound. It is because the DVD contains more information per frame than a CD. Try to watch the same movie recorded in a CD and DVD to find the difference.

6. The connectors: The components of the system need to be connected together. There are different methods of doing so. The display unit has its input composite, s-video, component, DVI [Digital Visual Interface] or HDMI [High Definition Multimedia Interface]. Generally,the DVD and TV have female connectors. So connect the male part to the right slot. The connectors are usually shipped free with each unit.