"What is Home Theatre?"
Home Theatre is the Hobby/Obsession of recreating the atmosphere of a Movie Theatre in the comfort of your own home. Either in the Lounge (Hobby) or a dedicated Home Theatre (Obsession).

The Home Theatre market in the UK is growing at an alarming rate. All the major Hifi & TV manufacturers are producing Multi Channel Surround Sound AV (Audio Visual) equipment. The "standard" configuration is "Dolby Pro-Logic" which is a 4 channel system with 5 speakers located around the room. The 4 channels are LEFT, CENTRE, RIGHT which are located in front of the viewer and the SURROUND channel which uses a Pair of speakers placed behind the viewer. This may or may not be augmented by a SUBWOOFER which provides extra impact for Low Frequency sounds e.g. Explosions, Earthquakes, Thunder etc.

The next step up the Cinephile ladder is THX. This is not so much a system but a specification which lays down minimum standards for equipment. THX was developed by Tom Holman at Lucasfilm (Tom Holmans eXperiment) and was primarily intended to ensure that when a movie was shown in a theatre it would sound the way the Director and Sound Engineer had intended.

"Dolby Digital" is the latest generation of Surround Sound of which the home version is called Dolby AC3. This gives 6 discrete channels of CD quality audio and is also referred to as 5.1
LEFT, CENTER, RIGHT, LEFT SURROUND, RIGHT SURROUND and SUBWOOFER


Thats the audio side of Home Theatre covered breifly, now for the pictures. Having got the BIG sound of a real movie theatre we now need the BIG picture. The bigger the better. I currently use a 28" Mitsubishi Nicam TV in my 12' x 11' Lounge which I view from a distance of about 7 feet. At present the largest direct view TV on sale in the UK is 37". Above this size you move onto projection TV. Toshiba are currently selling a superb 55" Nicam Rear Projection set with Dolby Pro-Logic for a mere 3500UKP. Images larger than this can be obtained using a Video Projector.
These come in 3 types:-

LCD (Liquid Crystal Display)
LCD Projector
Still in its infancy LCD technology uses a colour LCD panel through which is shone a very bright light source which is then focused onto the screen. This type of projector can suffer from the "Chicken Wire" effect. So called because the individual pixels of the display can be seen if the image is viewed too closely giving the impression that someone is holding a piece of chicken wire between you and the screen.
The "Newborn" display technology uses a DMD chip from Texas Instruments. This chip contains over 400,000 "Micromirrors" in an area about the size of your thumbnail. These mirrors deflect a light source to create the image. I have recently fitted 2 of these projectors and the image is vastly superior to LCD
DLP (Digital Light Processing)
DLP Projector
CRT (Cathode Ray Tube)
CRT Projector
Tried and trusted technology which uses 3 small (about 6-9") TV tubes 1 Red, 1 Green, 1 Blue to project 3 images onto the screen. These images need to be accurately converged to obtain a clearly focussed image but once set up correctly provide the best image. The only drawback of a CRT projector (or any projector to some extent) is that the room needs to be darkened slightly. But Hey! When was the last time you went to the movies and they left the lights on?
If you have enough money (won the lottery lately?) the image can be further enhanced by the addition of a Line Doubler or Quadrupler which digitally converts the 625 line TV signal into a 1250 line image giving similar results to 35mm film.


Thats the Viewing device taken care of but the image will only be as good as the source. I currently use a Mitsubishi M55 Nicam Video and a Pace MSS 500 Satellite Receiver for my movie sources. The best source is DVD (Digital Video Disc) which offers higher than broadcast quality movies on a 5" disc similar to an audio CD at a price slightly above VHS Videotapes.
My View (for what its worth)
Much hype surrounds the methods of interconnecting the various items of equipment. This involves "High Grade Interconnects" with directional arrows to indicate which way the signal should flow down the cable. As an audio signal is alternating current changing direction between 20-20,000 times per second, I fail to see how a piece of copper wire can be directional! Likewise, there is little point in using gold plated plugs when the sockets to which they are connected are nickle plated. In fact there is a greater possibility of a poor connection resulting from having 2 dissimilar metals in contact with each other.
Having said that, I do NOT take the cheapest option and connect my speakers with bell wire. I am a firm believer in using a substantial cable for connecting speakers, typically 2.5 sq mm. I also believe in having a sound system much bigger than you need.


Fact: An UNDER powered amplifier is MORE likely to damage your speakers than an Overpowered one run at a moderate level.

If you are driving a 60 watt speaker at 8 watts from a 10 watt amplifier any explosions or similar loud effects will result in the amplifier clipping, giving at best a severely distorted sound and at worst resulting in the destruction of the tweeters. This happens because when an amplifier goes into clipping the output is rich in high frequencies (which may be so high as to be inaudible) that overload the tweeters. The tweeter in a 60 watt cabinet may only be rated at 10 watts as most of the energy in an audio signal is at the low end of the range. By comparison, a much larger amplifier e.g. 100 watts will reproduce the peaks without distortion. This may overload the bass driver momentarily but as long as this is not sustained, no damage will occur. Because there is no distortion the rest of the system will not be overloaded. The end result is a much cleaner sound with the ability to blow your socks off!

At the end of the day sound and picture quality is very much a subjective issue. What looks and sounds perfectly acceptable to one person may be totally unacceptable to another. However some people (with more money than sense) simply must have the most expensive. They then spend all their time looking and listening for imperfections in the performance. This to me is totally missing the point. The best advice I ever heard was


"Stop spending money when YOU can notice no improvement"

Sit back, Dim the lights, Pump up the volume and enjoy the movie!

The views expressed on this page are worth exactly what you paid for them!


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This page last updated : 5th October 2000