Home Theatre (often known as Home Cinema in the UK 'cos we go to see films in the cinema, not the movie theatre) is what its name implies - a movie theatre at home. Of course, you haven't got a huge screen at home, but the idea is to get as close as possible.
There are a number of key parts of a home theatre system.
The Screen
The screen is what you watch your films on! Essentially, any television screen will do, but the bigger the better. It also makes a lot of sense to get a widescreen TV as almost all films nowdays are shot in 16:9 (or even wider).
There are a number of excellent traditional (CRT) TVs around - for example the SONY WEGA range. Those with more money would head towards a plasma screen - bigger and no more than few inches deep. The other option is a projector which needs semi-permanent mounting and a dark room with a decent screen (a white wall is only just about usable). And while projectors cost less than plasma screens, their bulbs have a very limited life and are very expensive to replace.
The video source
The video source is almost always a DVD disk. Most modern DVDs, apart from having high quality video, also have the audio in true 5.1 channel Dolby Digital. When coupled with an appropriate sound system (see below), this really makes the home theatre experience.
In the early days of home theatre, laservision video discs were also used, but they are pretty well obsolete by now. Video tapes can also be used, and with a Dolby ProLogic decoder (also usually built into the audio units), you can get pseudo 4 channel sound.
You can also purchase a DVD recorder, although any recordings from broadcast TV will only be with as many audio channels as the broadcast signal. If the signal includes digital audio (such as the NICAM system in use in the UK) then this should be encoded directly on the disk without going via an analog stage).
The audio system
As mentioned above, most DVDs have a full 5.1 channel Dolby Digital soundtrack. The channels are as follows.
- (Front) Left
- (Front) Right
- Centre
- Surround (Rear) Left
- Surround (Read) Right
- LFE (Low Frequency Effects - the subwoofer).
The LFE channel is the .1 as it's not a full frequency range. This is the basic configuration you'll find in modern cinemas. Dolby EX adds a central rear channel, making 6.1, and SDDS (Sony Dynamic Digital Sound) adds two additional front channels. But these aren't really supported (and in my opinion, necessary) in a home setup.
The Audio decoder has to split up the digital source into the 6 channels, and then feed it to six amplifiers and out to six speakers (or on some systems, it only has five amplifiers and a line-level out to an active subwoofer with its own built in amplifier). If the DVD player and audio decoder are separate units (as is advised), then the link between them should be digital. This can either be coax or optical. The general view is that coax actually gives a better result, but can only run 1-2 metres, and longer than this should be optical.
Speakers
If you have six channels of sound, you need six speakers! The layout should resemble this.
+------------------------+
+ SUB CENT +
+ +------+ +
+ FL + TV + FR +
+ +------+ +
+ +
+ +
+ +
+ +
+ +
+ +------------+ +
+ | COUCH | +
+ SL +------------+ SR +
+------------------------+
- SUB - Subwoofer. Exact location isn't important.
- CENT - Centre (dialog) speaker.
- FL / FR - Front Left / Front Right.
- SL / SR - Sorround (rear) Left / Surround (read) Right.
The front two, and the rear two speakers should be the same type (and often all four corner speakers are). The centre speakers are often manufactured specifically to be centre dialog speakers and should be located directly above or below the TV.
Cost cutting
In an ideal world, you should purchase a lot of separate parts.
- A DVD player (or recorder).
- An AV decoder.
- 4 corner speakers.
- 1 dialog speaker.
- A subwoofer.
(Of course, you need a TV as well but that's a separate item.)
This can come to a huge amount of money. The cheapest way to do the whole thing is to buy an "all in one" home cinema system. This would usually be an integrated DVD player / AV decoder, and six speakers (often in this case, the subwoofer isn't active). However, the overall quality won't be that high.
The other option is to buy three items - the DVD player, an AV decoder and a "speaker set" which includes all 6 speakers. Ensure that if your AV decoder has a line-level output for the subwoofer, the subwoofer you buy is active. This way round is probably the best price/quality compromise.
However, the more you spend, the better quality system you will get. If you're buying a system just to stick in your lounge, £500 is probably the most it's worth spending. If, on the other hand, you're setting up a dedicated home theatre room, you'll appreciate the extra expenditure.
Sources - the research I've just done to put together my new system.
- DVD recorder: Toshiba DR3
- AV decoder: Sony STRKSL500
- Speaker set: Sony SPSL2
Update on 7th June 2005 - I changed the DVD recorder for a Toshiba RD-XS34. There was nothing wrong with the DR3, but I decided it was worth spending the extra money for a unit with a hard disk.